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Catalysis – Key toa Sustainable Future

Science and Technology Roadmap for Catalysis in the Netherlands

January 2015

Catalysis – Key to a Sustainable FutureScience and Technology Roadmap for

Catalysis in the Netherlands

Colophon

Commissioned byThe Dutch Ministry of Economic AffairsThe Netherlands Institute for Catalysis Research (NIOK)The Industrial Advisory Board of NIOK (VIRAN)

Writing, Editing, Visualization

Core teamDr. M. Barroso (Utrecht University)Prof. J.H. Bitter (Wageningen University)Dr. Q.B. Broxterman (DSM Chemical Technology R&D B.V.)Prof. B. de Bruin (University of Amsterdam)Dr. F.R. van Buren (retired from Dow)Prof. U. Hanefeld (Delft University of Technology)Prof. E.J.M. Hensen (Eindhoven University of Technology)Prof. S. Otto (University of Groningen)Prof. E.T.C. Vogt (Albemarle Catalysts B.V., Utrecht University)Prof. B.M. Weckhuysen (Utrecht University)

Project managerDr. W. Hesselink (retired from Shell)

Support officeDr. I.H.L. Hamelers (NWO)Dr. I.S. Ridder (NWO)

Text editing and adviceThomas SB Johnston, Johnston Text & Training

DesignWAT ontwerpers, Utrecht

Printed byZalsman B.V

The Hague, January 2015

1 Setting the Scene of the Roadmap 5

2 Approach 10

3 Fossil Raw Materials 13

4 Biomass and Renewable Resources 21

5 CO2 Conversion and Solar Energy Storage 29

6 Catalytic Synthesis of Bioactive Molecules 37

7 Precision Synthesis of Functional Materials 45

8 Integrated Multi-Catalyst Multi-Reactor Systems 53

9 Fundamentals and Methodology 61

10 Annexes 69

List of contributors 70

Background documents 71

Abbreviations 72

Contents

5

Catalysis – Key to a Sustainable Future | Setting the Scene of the Roadmap

Setting the Scene of the Roadmap

Today’s society needs to prepare itself for a more

healthy future with food for all and plenty of

energy and resources to fuel our growing

prosperity. The field of chemistry is ready to take

on this global challenge. In particular, catalysis is

a crucial discipline when it comes to providing the

scientific and technological foundation for making

cleaner, more efficient, and economically viable

chemical production processes. In this document,

the Dutch catalysis community presents its 2nd

Science and Technology Roadmap for Catalysis for

the next 20 years and describes how it will treat

the feedstocks of the future, how it will use

catalysis for the production of transportation

fuels, bioactive molecules and materials, and how

it will further integrate reactions, catalyst

materials, reactors, and production processes at

all length scales of importance.

In its Horizon 2020 Framework Program, theEuropean Union has defined seven societalchallenges that will guide research-and-development efforts in the decades to come.Chemistry in general, and catalysis in particular, isdirectly relevant to most of those, e.g. in the way wedesign and synthesize materials for energy storage.Or in how we will re-think our production processesin a biobased economy, where the main source ofall our chemical building blocks will no longer befossil but biomass. Chemistry is also directly relatedto the way we are going to design products andprocesses with optimal resource efficiency, usingthe byproducts as secondary raw materials for otherprocesses rather than simply creating waste likeCO2. This is a prerequisite for a circular economy.Furthermore, chemistry plays a pivotal role in thechallenges regarding transport and health. Considerthe development of new fuels and fuel cells, forexample, or synthetic biology and the synthesis ofbioactive molecules such as antibiotics. As over 85%of all chemical products today are produced viacatalytic reactions, new developments in all fields ofcatalysis will have a huge impact in tackling theabove-mentioned challenges.

In the Netherlands, the national government,environmental NGOs, trade unions, energyproducing companies, chemical companies, andmany other organizations agreed on a highlyambitious Energy Initiative in 2013. That set atarget of reducing energy consumption by 100 PJ by2020 but also ensuring a 16% share for renewablesin energy production. In the long term, by 2050, theNetherlands’ energy supply system should beclimate neutral. Given these high ambitions and theapparent lack of a long-term strategy for achievingthese goals, the government was advised to draw upan authoritative Innovation Agenda. Anotherrelevant ambition was put forward by the Dutchchemical industry (VNCI) in its Roadmap, namelyto have reduced its emission of greenhouse gases by40% by 2030. Recent German and BritishRoadmaps have put forth the huge potential ofcatalysis as a way to reduce the energy intensity andgreenhouse-gas emissions of the chemical industry.Game changers could include the use of biomassfeedstocks and the production of hydrogen fromrenewable energy sources, as well as the directutilization of CO2 in chemical synthesis. Thesewould provide new routes for making fuels andchemicals in a truly sustainable way.

These worldwide and national considerations arenicely complemented by the recent Vision 2025 forChemistry and Physics within the Netherlands,developed by the Dutch chemistry and physicsresearch community. It defines a research agendawith seven grand challenges for Dutch chemistryand physics, including Sustainable (Bio)ChemicalProcess Engineering, Advanced Materials, andEnergy. For Energy, it argues that a “transition tosustainable energy conversion and storage isrequired due to finite reserves of fossil fuels and theimpact of climate change. This transition is of sucha scale that it requires extensive short- and long-term research in physics and chemistry (combinedwith other sciences). In the short term, newtechnologies will extract and convert solar energy

6

Seven Societal Challenges in Horizon 2020

1. Climate action, environment, resource efficiency andraw materials

2. Secure, clean and efficient energy

3. Food, agriculture, marine and maritime, inland waterresearch, Biobased Economy

4. Smart, green and integrated transport

5. Health, demographic change and wellbeing

6. Secure societies

7. Europe in a changing world – inclusive, innovativeand reflective societies

more directly, whereas biomass or re-use of carbondioxide will be the key resource for manychemicals.” Catalysis, being a truly interdisciplinaryresearch effort, is a key technology in thistransition. In addition, the Top Sector Chemistry,as installed by the Netherlands Ministry ofEconomic Affairs, has realized the (economic) valueof the grand challenges in this “Vision 2025”.Consequently, it selected Chemical Conversion,Process Technology & Synthesis and AdvancedMaterials as two of its spearheads for futuredevelopments within the Netherlands. The presentRoadmap for Catalysis aims to do the groundworkfor this strategic planning. It could well form thefoundation for new public-private partnerships andother research activities revolving around catalysisin the Netherlands.

With a turnover of € 60 billion (8% of GDP) thechemical industry in the Netherlands is animportant economic factor. Catalytic processes areof utmost importance for this industry: 85% of thechemical products are manufactured usingcatalysts. Also in the energy sector, e.g. inrefineries, catalysts play a key role. The chemicalsector aspires to grow during the next decades, andbe active along the entire value chain fromfeedstock to end-user market. Research anddevelopment in catalysis can be a key enabler forthis process. A significant contribution ofsustainable bio-feedstock for the chemical industrywill require robust catalytic conversion processes.New generations of catalysts will enable energy-and atom-efficient production processes. And, bysuccessful cross-disciplinary cooperation, catalysiscan contribute to new developments in materialsand life sciences.

Chemistry in general – and catalysis in particular –has a rather unique position in the Netherlands,just as the Netherlands has a rather unique positionin the international catalysis community. Pastinvestments, both in academia and in industry,

have created an excellent science and technologybase for catalysis research and development.Exemplary in this regard are the NetherlandsResearch School Combination Catalysis (NRSCC)and the Netherlands Institute for CatalysisResearch (NIOK), with its Industrial AdvisoryBoard, VIRAN. Together, they initiated the firstTechnology Roadmap Catalysis in the Netherlandsin 2001. The evaluation of the previous Roadmap issummarized beneath.

The first Technology Roadmap Catalysis set anexample for a number of international Roadmaps inthe decade that followed. This has given what isreferred to as the Dutch school of catalysis areputation as a world leader in science, and thecountry is still home to many large chemicalindustries. This position at the internationalforefront calls for a constant influx of intellect andideas, but also investments. The Dutch innovationecosystem is collaborative in nature; in academia,cross-disciplinary research programs have been setup, for example between chemistry and (reactor)engineering or between chemistry andbiotechnology. At the same time, and especially inthe field of catalysis, the Netherlands has a strongtradition of successful public-private-partnershipresearch programs, such as IOP Catalysis (1989–

7


Evaluation Technology Roadmap Catalysis 2001

• The Roadmap gave rise to three ACTS research pro-grammes: IBOS, ASPECT and Sustainable Hydrogen

• The update of the Roadmap in 2006 led to the initia-tion of the SMARTmix programme CatchBio

• The Roadmap has increased the international visibil-ity of the Dutch school of catalysis

• The Roadmap has strengthened the cooperation be-tween the Dutch chemical industry and universities

• The Roadmap was highly ambitious – good progresswas made but many goals were only partly achieved

1998), ACTS (2002–2013), and the public-privateprograms NIMIC and CatchBio (2008–2016). Nowwe need to extend this collaborative effort toinclude innovative SMEs, we need to strengthenalready very promising research directions, and weneed to expand in newly emerging research-and-technology avenues in which the Netherlands canmake valuable contributions. All this forms thebasis for the newly developed, and thereforesecond, Science and Technology Roadmap forCatalysis.

Working together, academic and industrial partnershave created the present Roadmap. It presents thecurrent scientific and technological challenges andopportunities for seven specific topics in catalysis inthe Netherlands, describing for each topic a numberof exciting future research directions and offering abrief outlook on the results that those may deliver.All of the proposed areas of research and theresulting products are driven by our ambition tocreate clean, efficient production processes that areeconomically viable. In biomass conversion, forexample, this means that we propose to work ongaining a detailed understanding of catalysis,process technology, agriculture, and biomassproduction chains. And that we propose to directour efforts to converting carbon dioxide intochemical building blocks and energy carriers using

renewable energy sources, as this is essential tocope with the negative impact of increasingatmospheric CO2. This would clearly contributetowards tackling the challenges the EU faces interms of clean energy as well as resource efficiency.The example also nicely demonstrates theintegrated approach in which different (sub-)disciplines all contribute to the same challenge. The other topics in this Roadmap relate to thesocietal challenges in a similar way. They includefossil resources (Chapter 3), the catalytic synthesisof bioactive molecules and functional materials(Chapters 6 and 7), the integration of multi-catalyst, multi-reactor systems (Chapter 8), andrelated experimental and theoretical methods(Chapter 9).

Across all topics, we have chosen to apply a threestage systems-catalysis approach in which we

8

’89 ’90 ’91 ’92 ’93 ’94 ’95 ’96 ’97 ’98 ’99 ’00 ’01

Start IOP Catalysis NIOK VIRAN

NRSCC

Technology Roadmap Catalysis (TRM)

Figure 1.1 Timeline showing important events for the Dutch catalysis community

Three-stage systems catalysis approach

1. Fundamental understanding of the catalytic system

2. Predictive theoretical multiscale model of thecatalytic system

3. Design of knowledge-based synthesis strategies thatcan be controlled that can be controlled at thedifferent length scales required

consider the catalytic process from the nanometeror atomic detail of the reaction to the meter scale of the reactor as a whole. A fundamentalunderstanding of the reaction in real systems under process conditions is acquired throughsophisticated analytics, e.g. operando microscopyand spectroscopy. This is then followed by thedevelopment of a predictive theoretical model thatspans all relevant length scales and containssufficiently detailed chemical descriptors of thecatalytic reaction and related reaction steps. Fromthese descriptors a knowledge-based synthesisstrategy is developed for the desired molecule or material.

The key to such an integrated systems-catalysisapproach is the ability and willingness tocollaborate between various disciplines andbetween academic and industrial research and

development. The Netherlands is uniquelypositioned to make this approach work: most of theinfrastructure is already in place, industrial andacademic groups work closely together (bothgeographically and culturally), and they have anexcellent track record in terms of collaborativeresearch-and-development efforts.

Finally, the historically strong position of Dutchcatalysis coincides with an excellent level ofintegrated chemical education in the fields ofcatalysis and process development. Manyinternationally top-class students are attracted atvarious educational stages (MSc, PhD and PD) tothe top groups at Dutch universities, which as aresult have been able to deliver many successfulresearchers to academia and industry. Thiseducation could be enriched by instilling knowledgeof additional fields like intellectual property andmarketing. The present structures we have in theNetherlands for integrating all aspects of catalysisin teaching and research are unique, and need to benurtured and strengthened.

9


’02 ’03 ’04 ’05 ’06 ’07 ’08 ’09 ’10 ’11 ’12 ’13 ’14 ’15

ACTS Update TRM Catalysis CatchBio

NIMIC

TASC

Zwaartekracht consortiumNetherlands Center

for Multiscale CatalyticEnergy Conversion

Science & TechnologyRoadmap Catalysis

Topsector Chemie

Zwaartekrachtconsortium ResearchCentre for FunctionalMolecular Systems

Unique qualities of Dutch school of catalysis

1. Infrastructure in academia and industry is in place

2. Industrial and academic groups work close together,geographically and culturally

3. Excellent track record in collaborative research

4. Excellent level of academic education

10 Approach

11

Catalysis – Key to a Sustainable Future | Approach

In addition, the core team determined that the

Roadmap as a whole should help to strengthen the

Dutch catalysis community, lead to a greater

integration of the heterogeneous catalysis,

homogeneous catalysis and biocatalysis community,

provide opportunities to start collaborations with

other research fields (e.g. process technology,

biotechnology, physics) and help the community to

stay at the international forefront.

In January 2014, a workshop with 65 participants

(see Annex 1) served as the kick-off for the

discussions with the catalysis community. The

participants discussed the new trends in science, the

strengths and weaknesses of the Dutch academic

catalysis field, the major challenges facing society in

the coming years and what catalysis can contribute to

help solve those issues. In addition, they discussed

the opportunities for collaborating with other fields

of science to maximize the impact of Dutch catalysis

research. Based on this round of consultations the

core team concluded that there was consensus on

seven research topics to be included in the Roadmap:

Fossil Raw Materials, Biomass and Renewable

Resources, CO2 Conversion and Solar Energy Storage,

Catalytic Synthesis of Bioactive Molecules, Precision

Synthesis of Functional Materials, Integrated Multi-

Catalyst Multi-Reactor Systems, and Fundamentals

and Methodology. For each topic the core team then

developed a position paper. These were discussed

and reviewed by experts in the field. The results are

presented in Chapters 3-9 of this Roadmap. Each

chapter presents a brief description of the state of the

art and current challenges and opportunities for

catalysis. Subsequently, the specifics of the Dutch

situation are highlighted. From this, a selected

number of research areas are derived with a set of

related deliverables.

AimSince 2001, the year in which the previous Roadmap

was presented, the world has undergone significant

changes in terms of important societal issues, the

economic situation, the structure of research funding

and the interests/strategy of industry (including the

chemical industry) in the Netherlands. In 2013,

together with the Top Sector Chemistry, the Dutch

catalysis community, represented by NIOK and VIRAN,

decided to create a new Science and Technology

Roadmap for Catalysis, which would build on this

changed situation. The aim of this report is to

develop a vision of catalysis research in the

Netherlands for the next 10 to 20 years.

ProcessIn order to realize this new Science and Technology

Roadmap for Catalysis 2013, NIOK and VIRAN

appointed a core team of scientists from academia

and industry for developing the Roadmap. The core

team was supported by a project manager, a process

manager, and the NIOK/VIRAN office. The names of

the members of the core team and the support team

can be found in Annex 1 of this Roadmap.

During the first stage in the development of the

Roadmap, the core team determined the criteria to

be used in identifying which topics the Dutch catalysis

community should work on in the coming years. The

criteria were as follows:

• The topics should describe exciting new directions

for world-class research that will help to solve a

current technological and/or societal challenge and

should fit in with the strengths and expertise

currently present in catalysis in the Netherlands;

• The topics should be driven by the ambition to

create clean, efficient production processes or

products that are economically viable.

Fossil Raw Materials

The conversion of fossil raw materials to fuels

and chemicals will remain important for at least

the decades to come. In view of the enormous

volumes of converted materials, even minor

improvements will have a substantial impact.

In view of geopolitical developments such as

the recent use of shale oil and shale gas, this

market is a highly dynamic one. We will need

new catalysts for the activation of methane but

also other C1 carbon sources, including CO2, as

well as more flexible and robust catalysts and

processes for the conversion and cleanup of

heavy feedstocks. We also need to understand

the processes of catalyst deactivation and to

replace scarce raw materials, such as noble

metals, for catalyst manufacture.

13

Catalysis – Key to a Sustainable Future | Fossil Raw Materials

Status & Challenges

Current SituationThe use of catalysis in support of the conversion offossil fuels may appear to be relatively mature, yetthere are clear developments that requirefundamental improvements in this field. Theamount of crude oil refined every day worldwideamounts to about 85 million barrels. This impliesthat even the smallest improvements in selectivityor effectiveness in the processes used translate to asignificant impact.

Solid, liquid, or gaseous fossil raw materials are,and will remain, the main sources of raw materialsfor the production of transportation fuels andchemicals in the foreseeable future. Although oiland gas production may peak during the next twodecades that will not diminish their role. Especiallygas (methane) will become more important, asexplained below in more detail. The quality of crudeoil will decline, and disadvantageous crudes will bebecome more attractive for conversion. This willrequire more stable catalysts with improvedresistance to poisons. Gas, and particularly shalegas, will become more important in the near future.

Due to its local availability, shale gas is likely todisrupt current economic balances. Since shale gasis relatively light and paraffinic, its use as a crackingfeedstock may lead to a shortage in olefins likepropylene, butadiene, and C4+ molecules,specifically aromatics, see also the challengesparagraph in Chapter 4 Biomass and RenewableResources. Other sources of methane, such as deep-sea hydrates or methane from permafrost, couldbecome relevant later on. Furthermore localsources of methane from the anaerobic conversionof biomass may become relevant from a raw-materials standpoint (valorization of fugitiveemissions). Coal may also become more important,especially in China, and will most likely be availablefor a very long period.

Oil- and gas-producing nations will claim a largershare of the value chain, and as a result, theproduction of base chemicals will move towardsthese countries. Smaller northwest Europeanrefineries and petrochemical complexes will likelybecome less economically feasible, so capacity willbe replaced by larger complexes in Asia and theMiddle East. The present oil- and gas-basedprocesses are at close to peak efficiency, but futurelegislation and for instance new engine designs may

14

Hirsa Torres Galves from the group of Krijn de Jong inUtrecht (Torres, H.M., et al. , Science 335 (2012) 835-838) designed supported iron nanoparticles as catalystsfor the production of lower olefins, and found effects ofboth particle size as well as promoter atoms. Thecatalysts displayed a remarkable selectivity towards lowerolefins in Fischer-Tropsch synthesis. The work wasperformed in the ACTS-ASPECT-program.

Lower olefins directlyfrom synthesis gas

Well-distributedFe NPs

Na/S addition

Inert Support

Inert

require different designs for future refineries toenable more flexibility. When a shift to new energycarriers (hydrogen, electrons, or new chemicalenergy carriers) is eventually made, a newinfrastructure will have to be developed. That, inturn, will mark the beginning of a new S-curve, withplenty of room for innovation, which is outside ofthe scope of this report, but even for conventionalenergy carriers based on renewable resources, the early part of the supply chain will have to be (re-)developed. The later stages of theinfrastructural chain can remain more or less thesame. Marine transportation fuels are the lastremaining fossil-based, high-sulfur fuels, and thesefuels will also require treatment to decrease sulfurcontent. Researchers are working on a catalyticsolution for this problem.

The subject of Fossil Raw Material conversion wasaddressed in Cluster I and Cluster II of the 2001Technology Roadmap. In Cluster I, a broadprogram on hydrogen was selected for execution,and subjects like CO2 sequestration were not widelyexamined. In Cluster II, mainly directed to theconversion of fossil raw materials to bulk chemicals,the ASPECT program was established. Thissuccessful program examined conversion to bulkchemicals in over 75 individual projects, 110scientific papers, and 3 patent applications.

ChallengesThe main challenges in replacing liquid fossil rawmaterials by gas or coal are the initial C-Hactivation and the thorough understanding ofcarbon-carbon coupling reactions. The same holdsfor a number of routes based on renewableresources. C1 chemistry as a whole is a majortheme, whether it be methane or methanol based,carbon monoxide based (Fischer-Tropsch) or evencarbon dioxide based. Fischer-Tropsch synthesis,especially from coal, will become more important inChina. A similar observation holds for the large

interest in methanol to olefins (MTO) in China.Process integration, separation andfunctionalization are relevant elements to improveon the present body of knowledge.

In the short term, the availability of shale gas maynegatively influence the availability of C4-C6building blocks (especially butadiene), which wouldresult in a demand for oligomerization catalysts andprocesses starting from e.g. ethylene or evenethane. At the same time, there will be an increasedneed for hydrogenation and dehydrogenationprocesses to balance the supply of and need forsmaller hydrocarbon building blocks.

Oxidative Coupling of Methane (OCM) has beenstudied extensively in the past as a way to activatemethane and produce larger molecules, but theselectivity and yield are still not high enough to besufficiently competitive with e.g. steam crackingbecause of the reactivity of the products towardsoxygen. This research line does not seem to offeropportunities, and should best be abandoned.However, the research has yielded valuable insightswith respect to the need for intimate couplingbetween catalyst and process, for instance incatalytically active membranes, which should betaken into account. This implies that research onintegrated systems is a promising field. In general,flexible integrated processes for the conversion ofgas to fuels and chemicals are required to be able to respond to fast-changing feedstock availability.One could think of flexible processes for convertingsmaller molecules to larger ones, the dehydro -genation or functionalization of alkanes, or animproved process for catalytic steam cracking withadded product flexibility. Although the latter is atough challenge, steam cracking is one of theprocesses that would benefit most from catalysis,especially from an energy standpoint, throughlower temperature and through selectivity control.

15


The use of diesel as a transportation fuel isbecoming more important in the US. In the presentsituation, gasoline is transported from Europe tothe US, and diesel is shipped back. With theincreasing demand for diesel in the US, this cannotbe maintained, which is creating an imbalance inrefinery outputs. This generates the need for newprocesses that have a higher selectivity to diesel atthe cost of gasoline, such as diesel-selective FluidCatalytic Cracking (FCC) or hydrocracking.

For the conversion of coal, improved catalyticprocesses like hydrogenation, sulfur resistantgasification, and methods for the selectiveconversion of aromatics from coal tar are relevant.

In conventional processes, a lot of money (bothinvestment costs and running costs) is spent onseparation. Avoiding separation steps, either bydesigning catalysts and reactors that can handlecomplex mixtures of raw materials or by couplingcatalytic solutions with separation technology in theprocess, would be very worthwhile. We could thinkof the oligomerization of untreated shale gas,olefinicity changes in mixtures of alkanes andalkenes, etc. It would also be interesting to look atways of introducing energy only at the catalytic site,i.e. without heating up the whole medium.

Opportunities for CatalysisThe overviews presented in the previous twosections provide plenty of opportunities forcatalysis. In view of the increasing effort requiredfor the conversion of ever-heavier and moredisadvantageous crudes, improved catalysts forheavy-oil conversion are needed. These will requireincreased porosity to avoid mass transferlimitations, and at the same time they will need tobe more resistant to poisoning and deactivation.There may be some options for homogeneoussolutions in this field, as evidenced by the ENISlurry Technology process, for example, in which

dispersed catalysts are used in the hydroconversionof heavy feedstocks.

Related to this, the cleanup of feedstocks willbecome more important. Low levels of impuritiescan travel through the installations and show up inunexpected and unwanted places. Apart from theobvious impurities, sulfur and nitrogen, alsoantimony, arsenic and mercury are important inthis respect.

Fundamental research on catalyst fouling,deactivation, feedstock variability, mechanicaldeactivation, breakthrough curves, roles ofcontaminants in catalyst stability, etc., is required.This also implies a challenge in analytical research,where new (micro-) spectroscopic techniques canbe used to increase our understanding of catalysts(and their deactivation) on all length scales, see alsothe challenges in Chapter 9 Fundamentals andMethodology. These techniques can also increaseour fundamental understanding of the effect ofpromoters. Apart from feedstock cleanup, thecleanup of waste streams, i.e. environmentalcatalysis, is a still increasingly important field.Catalysts and processes for the in situ (pre-)treatment of crudes will improve transportabilityand recoverability.

Flexible systems and processes would allow for arapid response to the changing availability offeedstock, for instance in catalytic steam crackingas described above. Current large-scale processestarget steady state operation, and transients lead toconsiderable off-spec production. More flexiblesystems and understanding of the transient stateswould be welcome, see also the challengesparagraph in Chapter 8 Integrated Multi-CatalystMulti-Reactor Systems.

Steam cracking is one of the most energy-intensiveprocesses in current petrochemical complexes.Developing a more energy-efficient process with an

16

improved selectivity to the desired products likeethylene would be a great opportunity for catalysis.The scale of operations and multipliers in refineryand petrochemistry are so large that even relativelysmall improvements will have a large impact, alsoon CO2 emission.

Dutch Strengths inFossil Raw Materials

The Netherlands does not have access to a largefossil fuel deposit, except from natural gas andpresently unused coal. The development of shalegas is still under debate. Historically, Dutchresearch has made considerable contributions tothe conversion of coals and methane. As the worldaround us is shifting to the use of C1-sources(methane and coal) we believe the research onmethods for gas conversion and carbon-carboncoupling should be intensified.

The Netherlands is world-leading in catalysisbecause it has high-level groups focusing oncharacterization, understanding and application, aswell as a large catalyst manufacturing industry.Industrial research has partially left applicationresearch, and the gap has not been completely filledby academia. Therefore, future strategy shouldfocus on maintaining the very good interactionbetween industry and academia.

The Dutch catalysis community also has a stronghistory when it comes to the fundamental sciencebehind catalyst preparation. The cooperationbetween industry and academia in this field shouldbe given the opportunity to flourish. Thecombination of theory, high-resolution analysis,and 3D atomic-precision catalyst preparation formaking tailored, structured systems provides a setof tools for better understanding of thefundamentals of catalyst preparation. Thisunderstanding will fill the gap between 2D modelsand practice.

17


Jana Schäferhans, working with Prof.Gadi Rothenberg in Amsterdam,developed a Cu–Al bimetallic oxide“sponge” that outperformsconventional noble metal catalysts inpropane dehydrogenation. The catalystgives higher conversions even when thetemperature is 200 °C lower than theoptimal temperature for the benchmarkPt–Sn/Al2O3 catalyst (Chem. Eur. J.2011, 17, 12254-12256).

No Platinum neededPropane

Cu-Al oxide sponge

Propene + H2

Yet another major strength of the Dutch school ofcatalysis is its integration of catalysis and processdesign, especially in process intensification. Thiscan be used to create the desired flexibility infeedstocks and routes, for instance by couplingmodular (micro) reactor arrays. This integration ofcatalyst research with process design, whichtranslates to a multi-scale, multi-disciplineapproach to problems, is highly desirable.

The conversion of heavier feedstocks is a researchfield that is strong in the Netherlands, both inindustry and academia, with players such asAlbemarle, Shell and BASF as catalyst producers aswell as academic research groups in e.g. Delft,Eindhoven and Utrecht. This research needs todeliver catalysts and systems that can help bridgethe ever-widening gap between (heavier and dirtier)feedstocks and (cleaner) products. This requiresimproved hydrogenation, which in turn requires alow-cost and abundant source of hydrogen,cracking of lower-quality feedstocks, resistance toimpurities and poisons, and the ability to selectivelycrack and induce ring opening in (poly)aromaticsystems.

Research Areas &Deliverables

Areas of ResearchBased on the above discussion and balancing of theneeds and strengths, four priority areas of catalysisresearch have been identified. It should beemphasized that the scale of operation and themultipliers in this field (refinery andpetrochemistry) are so large that even relativelysmall improvements will have a large impact.

First, the development of flexible processes forconverting molecules will become even moreimportant than it currently is. At one end

of the spectrum, there are reactions like(de)hydrogenation and the functionalization of alkanes, methods for C-C-coupling and C2-oligomerization starting from CO/H2, CH4,C2H4, C2H6 or CH3OH, for instance for theproduction of C2-C4 olefins with a focus onmethane as the starting material. The integration ofcatalyst and process design will be instrumental increating the desired flexibility. At the other end ofthe spectrum, there is the design of robust catalystsand systems for heavy oil conversion that canbridge the widening gap between (heavier anddirtier) feedstocks and (cleaner) products arerequired. The effects of catalyst-structuralparameters and chemistry (including promoters) onthe stability and deactivation of catalysts, and theeffects of poisons are crucial in this respect.

Secondly, developing a more energy-efficient andselective catalytic modification of steam cracking,with less CO2 production, would be a greatchallenge for catalysis.

The third area comprises research into ways ofactivating CO2. These are discussed in Chapter 5CO2 Conversion and Solar Energy Storage.

A fourth area is research directed towards filling thegap between 2D models and practice by animproved understanding of the fundamentals ofcatalyst preparation through the combination oftheory, high-resolution analysis, and 3D atomic-precision catalyst preparation. The design andunderstanding of catalysts in refinery andpetrochemistry typically calls for (kinetic andmolecular) models spanning several orders ofmagnitude in length scales (from nanometers indescribing surface reactions, to meters in describingbed packing, hydrodynamics and strength). We willneed to bridge the temperature and pressure gap inspectroscopy and microscopy, and we will need tostudy real systems rather than model systems. Thisarea is further detailed in Chapter 9 Fundamentals

18

and Methodology. Just as fossil fuels are finite,some constituents of catalysts, such as noblemetals, several transition metals and evenphosphorous, are becoming increasingly scarce.Research lines investigating the application of moreabundant elements as active components incatalysts are very important.

Deliverables in 10-20 years

• Integrated flexible processes and catalysts forefficient carbon coupling, allowing rapid responseto changes both in raw material and energy input,as well as product functionalization. This willallow for the design of easily adaptable refinerycomplexes that can handle a greater variety offeedstocks;

• Robust, stable and efficient catalysts andprocesses for conversion of heavier and dirtierfeedstocks and coal, as well as catalysts andprocesses for in situ (or at least pre-transport)improvement of crude quality;

• Flexible and efficient catalytic systems orprocesses to allow rapid response to changingfeedstock availability. This applies especiallywhen European refiners apply mixes of biomass-derived feedstocks and conventional petroleumfractions;

• Optimized catalysts based on non-preciousmetals that can replace noble metals and heavytransition metals that are linked to health orenvironmental concerns.

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21

Catalysis – Key to a Sustainable Future | Biomass and Renewable Resources

Biomass and Renewable Resources

A detailed understanding of the fundamentals of

the various forms of catalysis, process technology,

agriculture, and biomass production chains is

essential if we are to arrive at an economically

viable and sustainable biobased economy.

Catalysis is key in those processes. The main

challenges for catalysis involving biomass and

renewable resources are 1) selectivity, i.e. how

to convert the complex biomass mixture to

the target molecules -either drop-in or new

molecules- in as few steps as possible thus

preventing intermediate separations and

2) stability, i.e. how to achieve a catalyst that can

handle “poisons” present in the biomass and that

survives the conditions needed to convert

biomass.

Status & Challenges

Current SituationIn the first Roadmap Catalysis biomass wasmentioned as one of the potential feedstocks to makefuels and chemicals. It was stated that “Biomass isincreasingly being used for power generation andfrom a fundamental point of view it should beconsidered for the production of chemicals.” (ClusterII - p47). Since then the appreciation of biomass as afeedstock became more prominent since it is arenewable feedstock and therefore contributessignificantly to sustainability.

All biomass is highly heterogeneous and generallycontains a fraction to be used for the production offood and feed, as well as residues and side productsthat are potential feedstock for materials, chemicals,fuels, and energy. For materials, chemicals, energy,and fuels production, the five main classes ofcompounds in the biomass that can be used arecellulose, hemicellulose, lignin, lipids, and proteins.

To valorize biomass three routes are envisioned, allof which contain catalytic steps i.e., the syngasroute, the pyrolysis route, and the low temperatureroute (see Figure 4.1). The first two routes breakdown the biomass either to syngas (route 1) or bio-oil (route 2), after which the further conversion issimilar to processes developed for fossil feedstocks.

However, these processes have a special edgerelated to catalyst stability. The third routemaintains as much as possible the functionalitiespresent in the biomass. The latter route needssignificant research input, also from catalysis, toconvert the complex biomass mixture to desiredmolecules. Yet, since the biomass is highlyfunctionalized, this route is very promising formaking (bulk) chemicals.

Up till now, the commercial valorization of biomassto fuel, chemicals, and materials has been narrowlylimited to a few value chains, and broadcommercialization has yet to come. So far,commercial applications include the fermentationof sugar to ethanol, lactic acid and succinic acid, thevalorization of vegetable oils and the modificationand use of natural fibers. Hence, we are often at thestage of explorative research, gaining knowledge onhow to selectively convert these resource classes.More often than not, model or pure compounds areused to develop new catalysts for biomassconversion, for example in the Dutch privatepartnership CatchBio (Catalysis for SustainableChemicals from Biomass). In the last stage ofCatchBio, more attention is being given to theconversion of real complex feedstocks, a step thatrequires further attention in order to arrive at aneconomically viable use of biomass.

22

Catalytic conversion

H2/CO

Pyrlysis oil Fuels

Low temperature

Figure 4.1 Three catalytic routes to valorize biomass

An initial set of platform molecules that can begenerated from biomass, in particular from sugars, hasbeen defined. However, this set does not yet cover aswide a range as that known for fossil resources. Nopreferred feedstock-product combinations have beendeveloped to maturity, which indicates that muchexplorative work is still needed.

ChallengesIf we concentrate on the products higher up in thevalue chain, i.e. chemicals and materials, usingbiomass as a resource brings up a couple of specifictopics. Bulk chemicals are facing the emergence ofcheap shale gas, which offers an opportunity forlower olefins (particularly ethene), but does noteasily deliver heavier chemicals such as C4+ andaromatics. Renewables may present an attractivealternative feedstock for the production of suchheavier chemicals in this case. With respect to theproduction of functional chemicals, the clearadvantage of biomass is that it contains a wealth offunctionalized molecules. In the production of(performance) materials, a main driver for the useof renewable resources is the customer-based needfor sustainable production at competitive costs.The conversion of only a limited number ofcomponents of the biomass does not lead toproducts at competitive costs. For example,cellulose as well as hemicellulose and lignin (i.e.lignocellulose) are affordable but prohibitive toupgrade, because 1) fractionation and gasification isexpensive and 2) biocrude is difficult to valorize. Inaddition, lignin depolymerization is difficult andleads to a complex product mixture. Pure and welldefined sugars made from the cellulose fractionsare costly to produce. Upgrading them is alsochallenging, mainly because this requires eithermultiple conversion steps (typical ofchemocatalysis) or a difficult product recovery fromdilute solution (typical of biocatalysis). Otherdrawbacks are that upgrading proceeds withmoderate selectivity (chemocatalysis) or with lowvolumetric productivity (biocatalysis). Currently,

the valorization of the lipid fraction of the biomassis a challenge which is related to the highproduction costs of the products. Typically, untilnow deoxygenation reactions with the use of costlyhydrogen are used to upgrade the lipid fraction.Therefore production routes based on fossilfeedstock are more competitive thus new catalyticroutes for lipid upgrading are needed to make theuse of lipids competitive. Proteins and theirbuilding blocks, the amino acids (only the non-essential ones should be used for chemicals), arepotentially suitable for bulk chemicals. However,cost-effective isolation and selective conversion arestill in their inception phase. Therefore anintegrated biorefinery approach is needed tovalorize all components in the biomass at theirhighest value. Please note that not only value butalso market volume should be taken into account. If we are to meet these challenges, the integration ofexpertise is imperative – not only within thechemistry and process-technology disciplines, butalso in a much broader sense.

So far we have discussed the technological issues,including the key role for catalysis. However,integrative thinking with respect to biomassproduction is also essential. To determine whichbiomass is available and how we can modify thatbiomass in such a way that feed, food, chemicalsand fuels can all be prepared in an economical way,input from the agricultural side is needed. Inaddition, since biomass suffers from seasonalvariation, the issues of transport and storage alsoneed to be addressed.

For catalysis, when dealing with the catalyticconversion of biomass as a renewable resource,three main challenges stand out: 1. developing stable catalysts, 2. going towards more selective reactions, and 3. integrating catalysis with separation.

23


These challenges are not uncommon to catalysis,but they have a specific edge with respect torenewable resources.

Opportunities for CatalysisThe use of biobased resources introduces newrequirements for the catalysts used. As for chemicalcatalysts, stability is a major issue, as they shouldfunction in a liquid (slurry), often an aqueous oracidic environment, and they should be resistant tothe relatively high ash content, which can poisonthe catalyst. Moreover coke formation resulting incatalyst fouling should be prevented. Thus studiesof catalytic behavior under both model and realconditions are essential. Concerning biocatalysts,the use of whole cells (in which the enzyme/biocatalyst is incorporated) is desirable if we wantto use them in a (one-pot) biotechnologicalenvironment or in a modular set-up operating intandem or cascade mode. The transport of thereactant and/or products into and out of the cell isstill a challenge and offers opportunities for catalystdevelopment. In the downstream processes theapplied catalysts have to tolerate the side products

of the upstream processes when one wants to omit(expensive) intermediate product separation.Finally, the new catalysts preferably contain onlycheap and widely available elements.

Going towards more reactant selectivity presents aspecific challenge for biobased conversions, ascrude biobased feedstocks are generallyheterogeneous in nature or at least multifunctional,e.g. purified carbohydrates. Their composition willvary depending on location, time of the year andproduction methods. Moreover, the advantage of abiomass feedstock, i.e. a feedstock containingcomplex and overfunctionalized molecules, can onlybe used to its full potential if we can convert thesemolecules selectively. Developing redox neutralreactions is beneficial since the use of (expensive)hydrogen can then be prevented.Cascading multiple conversion reactions andseparation steps could be an option to findeconomically viable process routes. The integrationof chemocatalysis with industrial biotechnologyapproaches is a promising option in the design of areaction cascade, as is the option to combine

24

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various types of resources, i.e. not only biomass, butalso fossil and CO2. Specifically for biorenewables,the integration of length scales of the process andcorresponding logistics is a challenge, e.g. in thedevelopment of local, small-scale productionprocesses.

When stable and poison tolerant catalysts andcatalytic process are developed, the range ofavailable feedstocks for making products(chemicals, fuels) desired by society becomessignificantly wider. For example, waste water whichstill contains organic matter can be used asfeedstock. A typical example is the use of wastewater containing volatile fatty acids (VFAs). TheseVFAs can be converted by micro-organisms topolyhydroxyalkanoates (PHAs). PHAs as such canbe used as polymers, though their properties haveto be improved. Alternatively, they can be used asfeedstock for the production of bulk chemicals bychemocatalytic processes. Paques, a Dutchcompany specialized in integrated water and gastreatment, is very successful in this area. In analternative route short VFAs can be converted bymicro-organisms to longer VFAs which can be usedas feedstock for chemicals and fuels production.Chaincraft, a recently founded innovative SME, hasdeveloped breakthrough technology to elongateshort VFAs. These examples show that biocatalyticconversions and chemocatalytic conversions can gohand in hand, demonstrating that waste streamscan be utilized to widen the feedstock scope.

Dutch Strengths inBiomass & RenewableResourcesFocusing on renewable resources as one of the keyareas in catalysis, the Netherlands will build on itsexisting and recently developed strengths that areoutlined below. Internationally renowned academic

expertise in agriculture, i.e. production of biomass,is present at Wageningen University that is nowalso a member of NIOK. This presents a clearstrength which ties the agricultural sector, a majorpartner in the Topsector Agrifood, closer tochemistry in general and catalysis in particular.Chemocatalytic biomass conversion is a topic ofresearch at all universities united in NIOK, e.g.pyrolysis research at the University of Twente andUniversity of Groningen as well the companyBiomass Technology Group, and the work onlignocellulose to produce sugars at EindhovenUniversity of Technology.

As a concept, the biobased economy is widelyrecognized and supported. Catalysis and industrialbiotechnology are key technologies in the biobasedeconomy. A large number of initiatives have beendeployed to develop this field in the Netherlands,such as the public-private partnership programsCatchBio, BE-Basic, the Carbohydrate CompetenceCentre, and the Protein Competence Centre. Bothacademia and industry are actively involved in allthese programs. The aggregate budget of these fourprograms totals around M€ 200, half of which hiscontributed by companies and academic institutesand the other half by the government (at thenational, provincial or municipal level). Otherinitiatives, such as the Biobased Delta in thesouthwest of the Netherlands, InSciTe in Limburg,and the Green Campus and the BioProcessFacilityin Delft all represent excellent examples ofinitiatives in which industry, academia andgovernment all collaborate closely. Each of theseinitiatives in fact builds on a broader basis ofexpertise in conversion technology and catalysis ingeneral, for which the Dutch school of catalysis isknown for more than 50 years.

In terms of logistics and infrastructure, the fact thatthe Rotterdam mainport is a major hub forfeedstock transportation across Europe means thatthe availability of renewable feedstocks is not as big

25


an issue as it may seem considering the smallamount of land area that is available for renewablefeedstock production in the Netherlands. Thepresence of large oil refineries in the Rotterdammainport is a unique bonus for Dutch horticulture.The refinery byproduct CO2 is transported to thegreenhouses in the western part of the country,where it is used as a resource for plant growth.


Areas of ResearchTo address the three catalytic challenges in thedevelopment of a mature biobased economy -stability, selectivity, and integration- seven areas ofresearch are defined:

• understand and control the reaction mechanismsand the catalyst functions such as hydrogenation,and acid/base-functions, for operation in water.This will aid the development of stable andselective catalysts;

• understand and control the catalyst selectivity,both chemoselectivity as well as regioselectivityfor overfunctionalized feedstock, as this will leadto fewer byproducts and thus a more efficientprocess in general;

• understand and control the catalyst stability toovercome typical issues with destruction, fouling,or poisoning of the catalyst in order to develop aneffective process;

• activate biomass, i.e. make the solid biomasssuitable for further conversion. By proper

26

Rob Gosselink, working with Prof. Bitter Utrecht/ Wageningen,(Gosselink, R. W, et al., Angew.Chem. 125: (2013), 5193–5196),demonstrated the use of tungsten-based catalysts for thedeoxygenation of triglyceride-based feedstocks. Changes in a (pre)treatment procedure areshown to control catalyst selectivity 1) to decarboxylation/decarbonylation products i.e. the carbon chain in the products is one carbon atom shorter as in the feedstock or 2) tohydrodeoxygenation i.e. the carbonchain in product is has the samelength as in the feedstock. Inaddition high yields of unsaturatedproducts even in the presence ofhydrogen can be achieved.

Tungsten-based catalysts for deoxygenation of triglyceride-based feedstocks

W2CHydrodeoxygenation

WO3Decarbonylation/decarboxylation

R

R

R

R

Non edible oils, fatty acids, esters

activation of the biomass downstream processingbecomes more facile i.e. more selective processcan be developed. Input from e.g. plant sciencesis essential;

• develop new catalytic routes to new moleculeswith predefined properties. The new moleculesneed to be defined in collaboration with industrialpartners;

• integrate the catalysis with separation technologyin order to mitigate the challenges presented byhigh dilution, feed contaminants/heterogeneityor abundant byproducts;

• integrate different forms of catalysis to arrive atmore efficient product formation.

Research in all these directions will benefit from aninclusive approach in which biocatalysis,homogeneous catalysis and heterogeneous catalysisare considered along with other scientificdisciplines and, if beneficial, integrated for thedevelopment of efficient, low-cost conversions.Moreover, we need to consider the options for theintegration of fossil and renewable feedstock for anoptimized product mix, i.e. one with the highestadded value. This means establishing whichresource (or mix of resources) can best be used in aspecific production chain.

Of course, issues with catalysis in general – such asthe replacement of scarce and expensive metals incatalysts and the development of dedicatedcomputational tools for modeling experimentalresults and for data handling – apply to renewablesresources just the same, see also the research areasparagraph in Chapter 9 Fundamentals andMethodology.

Deliverables in 10-20 yearsThe Top Sector Chemistry has set the ambition forthe Netherlands to be world-leading in greenchemistry by 2050. More specifically for thisRoadmap, a highly ambitious deliverable in 20years’ time will be the full use of industrial andagricultural waste streams as a resource in theproduction of chemicals and fuels. If we distinguishdeliverables per type of resource, i.e.(hemi)cellulose, lignin, lipids and proteins, wecome up with four deliverables in 10 to 20 years’time.

The biomass feedstock is complex and variable bynature. The main challenge is to convert thiscomplex feedstock into tailored products. To arriveat that point the deliverables will be:

• new catalysts with improved reactant selectivity,i.e. the catalyst converts only the desiredmolecules from the feedstock to the desiredproducts. Some of the (new) products still need tobe defined;

• understanding factors that determine the stabilityof catalysts under relevant biomass conversionconditions, i.e. stability in water, with respect topoisons and coke formation;

• integrated systems, i.e. integrating the unitoperations (biomass activation, conversionseparations) which make the overall processrobust and cost effective;

• integrated scientific knowledge by combiningdifferent areas e.g., plant sciences and catalysis.

27


CO2 Conversion and Solar EnergyStorage

The conversion of carbon dioxide into energy

carriers using renewable energy sources is

essential in order to cope with the negative

impact of increasing atmospheric CO2. It would

also solve the problem of storage of excess

renewable energy. In the short term, better

catalysts for electrolyzers need to be developed.

A sustainable solution to the energy challenge

involves the development of cheap photocatalytic

materials and their integration into solar-to-

hydrogen device with an efficiency of at least

20%. Together with catalytic technology for

chemicals production from CO2, such devices

could vastly contribute to the realization of a

more carbon-neutral chemical industry in the

decades to come.

29

Catalysis – Key to a Sustainable Future | CO2 Conversion and Solar Energy Storage

Status & Challenges

Current SituationThe annual anthropic emissions of carbon dioxide,deriving from combustion of coal, oil, and gas,currently amount to about 30 Gt and are expectedto grow substantially in the coming decades. Giventhe impact of CO2 emissions on the global climate,several strategies can be considered to reducefossil-carbon consumption. Higher efficiency inelectric-energy production from conventionalresources may contribute to this goal, as will a moreefficient use of energy. Another strategy underinvestigation is carbon capture and sequestration(CCS), because of its large potential for CO2storage. The use of renewable energy sources suchas solar and wind is currently being given greatattention in connection with the production ofelectric energy. In particular, photovoltaic (PV) celltechnology is expected to contribute significantlytowards replacing fossil fuels in the generation ofelectricity in the coming decade. As such, the directconversion of solar energy was identified as a longterm goal in the previous Catalysis Roadmap.However, this did not result in a large researcheffort at the time. A major question remains how toefficiently store excess renewable electricity. Onesolution is to convert it into chemical energy;indeed that is the only viable solution if one isdealing with large excess of electricity. As theintelligent use of renewable energy sources is a keyambition of the Top Sector Energy, this is clearly anarea with potential synergy with the Top SectorChemistry.

To reduce the adverse effects of atmospheric CO2emissions on the climate, increased attention iscurrently being given to the utilization of CO2. Wedistinguish three categories: (i) the reduction ofCO2 with renewable solar energy to fuels (“solarfuels”), (ii) the production of chemicals and (iii) anenhanced biological utilization. There are also

technological uses for CO2 as such, for instanceenhanced oil recovery. An important facet in thenew perspective of CO2 utilization is the conversionof excess electricity from renewable resources intopreferably liquid fuels. If large amounts of CO2could be converted into fuels, preferably types thatare compatible with our current energyinfrastructure, it would mark a significant steptoward cycling carbon in a way done by nature.Such approaches would reduce CO2 emissions andalso limit the extraction of fossil-carbon sources.

ChallengesThe conversion of CO2 into fuels involves itsreduction, which requires energy. This energycannot be derived from fossil resources as theamount of CO2 produced would be higher than thatof CO2 converted into fuel. Therefore, theconversion of large amounts of CO2 into fuelsshould involve renewable sources of energy such assolar energy, wind energy, hydroelectric energy orgeothermal energy. If done efficiently, theconversion of CO2 could also be a way to solve theproblem of how to store (excess) renewable electricenergy. The most obvious choice would be to targetliquid fuels such as hydrocarbons similar to currenttransportation fuels or methanol. Methanol wouldhave the added benefit of also being anintermediate for the production of a wide range ofchemicals. There are many ways to convert CO2 tofuels, such as direct reduction using electric energy,photocatalytic reduction, and chemical reductionusing H2. The technologies associated with theseapproaches have widely different levels of technicalmaturity. Currently, for instance, directphotocatalytic CO2 reduction can only be done atvery low efficiency, whereas using water electrolysisto produce H2 is proven technology, although notamenable to large-scale implementation becauseexpensive catalyst materials are used. In virtuallyall of these approaches, catalysis plays an importantrole with significant challenges for electrocatalysis,photocatalysis, and heterogeneous and

30

homogeneous catalysis. On a more general level,the intermittent operation of catalytic processesunder a daily cycle is becoming important, alongwith classic themes such as catalyst activity,selectivity and stability.

In a circular economy, CO2 is increasingly viewedby the chemical industry as a building block, ratherthan a waste product. In some cases, the use of CO2for the production of chemicals is already at thecommercial level. Efforts are underway to react CO2with olefins, dienes and alkynes to formcarboxylates, carbonates and carbamates. Many ofthese processes are catalytic. Some processes areendergonic and thus more difficult to implement.Currently, many chemical processes rely onsynthesis gas (CO+H2), e.g. Fischer-Tropschsynthesis, hydroformylation and carbonylation.Opportunities should be explored to developchemistry based on CO2+H2 instead of CO+H2 as away to functionalize hydrocarbons. However, oneshould keep in mind that the contribution of CO2

conversion to chemicals towards solving the impactof climate change is limited by the order-of-magnitude smaller size of the chemicals marketcompared to the fuel market.

Biotechnological conversion of CO2 involves the useof (modified) organisms to convert CO2 into usefulproducts under optimized conditions, e.g. thecultivation of biomass in greenhouses underincreased CO2 concentration, the growing ofaquatic biomass by dissolving CO2 in water, and thetargeted synthesis of chemicals. Modifying theorganisms by for instance genetic engineering isone of the possibilities to arrive at the rightchemicals. An example is the Photanol concept, aDutch SME that uses engineered cyanobacteria thatdirectly and efficiently turn CO2 into predeterminedproducts when exposed to light.

Opportunities for CatalysisThe technology for solar fuels production should berobust, scalable and efficient. It should have an

31


H2O

H2

Liquid fuels

Energy storage

Chemicals

Fertilliser

Sunlight or otherrenewable energy sourcesare used to produce smallcarbon-based compoundsfrom carbon dioxide and

water and/or hydrogen

Renewable energy storage in chemical bonds

Electricity generation (Fuel cell)

Sunlight or other renewable energy sources are used to split water into hydrogen and oxygen

PlasticsPharmaceuticalsOther Chemicals

O2

CO2

CO2

Fueling Station

operating life of longer than ten years and be basedon abundant elements, and the overall systemefficiency should be sufficient for it to be able tocompete with non-sustainable energy generation.The intermittency of sustainable electrons will posechallenges to the future catalytic processes thatstore electricity. Direct electrochemical CO2reduction will require breakthroughs in the field ofelectrocatalysis and is considered a long-termtarget. The most likely scenario, therefore, involveswater electrolysis by renewable electrons generatedby photovoltaics technology or direct photocatalyticwater splitting to produce the H2 needed for thereduction of CO2.

The large-scale implementation of electrolyzers forrenewable H2 production is hampered by the lowabundance of active and stable electrocatalysts andtheir inability to deal with fluctuating conditions.Noble metals are most active for the difficultoxygen-evolution reaction. RuO2 is the most activematerial, but it degrades. Usually, titania-stabilizedIrOx is used for oxygen evolution, while Pt is usedfor hydrogen evolution in an acidic electrolyte.

Alkaline electrolytes allow the use of moreabundant materials (such as nickel, for both anodeand cathode) but still suffer from an order-of-magnitude lower current. Nevertheless, alkalineelectrolyzers form a very active field of research.

Integrated photocatalytic devices are increasinglybeing considered as an attractive alternative. Thereare many opportunities for improved materials forlight absorption, better catalysts for water oxidationwith low overpotential, the use of non-noble metalcatalysts and their integration into devices in whichaspects as light management also need to beconsidered. With regard to light absorption, thecurrently available semiconductors are eitherrobust but not very efficient (e.g. TiO2, Fe2O3) orefficient but unstable (e.g. CdS, CdSe). Tandemdevices are needed to reach efficiencies that cancompete with PV technology. Specific challenges tocatalysis are the development of better catalysts toreduce the overpotential of water splitting,especially the water oxidation reaction, and to buildsmart interfaces between photoabsorbing andcatalytic layers.

32

Fatwa Abdi (MECS group, Bernard Dam,TU Delft) designed a water splittingdevice with a 5% solar-to-hydrogenconversion efficiency using a spraydeposited BiVO4 as the photoanode.This high bandgap material captures thehigh energy photons and takes care ofthe oxidation of water. The low energyphotons are converted by the Si-based PV solar cell which assures the proper potential for the waterreduction at the other electrode. NatureCommunications 4 (2013) 2195.

Efficient solar water splitting

All of these aspects should preferably be addressed inan integrative manner. It requires input from thoseworking at the device level, implying that designcriteria for the optimal device need to be assessed apriori or along the way. It also requires closeinteraction between those working on the design ofnew semiconductor materials, (electro)catalysts, andon light and device management. Disciplines withinthe catalysis domain around in situ spectroscopy -tostudy elementary processes-, theoretical chemistry,e.g. to deal with excited states, and model studies ofthe cocatalyst/protective layer/semiconductorinterfaces, e.g. surface science, need to bestrengthened. Moreover, such an approach createsopportunities for scientists in the field of catalysis tointeract with those in the fields of photo(electro) -chemistry and nanoscale preparation techniques fordevice development (lithography, atomic layerdeposition, etc.).

If H2 could be cheaply produced from solar energy,the production of synthesis gas from CO2 would bewithin reach. From synthesis gas, a wide range ofproducts (methane, methanol, liquid hydrocarbonfuels) can be manufactured with establishedcatalytic technology. Nevertheless, issues remain tobe solved with respect to scaling such operations tothe optimum in terms of local/centralized H2generation and allowing for the variable processconditions associated with the intermittentavailability of H2. Another aspect of photocatalyticreduction processes of water or carbon dioxide isthat pure oxygen can be obtained as a byproduct.This byproduct stream has economic value, becausethe alternative route, via air separation, is veryexpensive.

Catalytic CO2 conversion to chemicals is rapidlydeveloping and new developments are dominatedby homogeneous systems, which can selectivelyreduce CO2 or build CO2 in other molecules. Thechallenge here is to widen the scope of reactionsand products and to develop more active and

selective catalysts. The use of heterogeneoussystems for this purpose is underdeveloped, exceptin already existing industrial processes, such asmethanol synthesis.

CO2 is not the only option for storing excess energyin the form of chemical energy. Anotheropportunity is to use abundant nitrogen as thefeedstock. It shares with CO2 conversion theopportunity to use abundant stable chemicals asfeedstock to fuels and chemicals.

Dutch Strengths in CO2 Conversion andSolar Energy StorageThe strongest asset to tackle the challenge of CO2conversion and excess renewable energy storage isthe existing Dutch network in catalysis, whereacademia and industry have teamed up and have anexcellent track record in the successful integrationof different disciplines to cope with importantsocietal challenges. The most recent example is theestablishment of a graduate school on solar fuelscatalysis aimed at educating young scientists in thisnew field. Research groups from Leiden University,Utrecht University, Eindhoven University ofTechnology and University of Twente participate inthe graduate school.

So far, the chemical industry has largely shunnedsignificant efforts in terms of CO2 valorization,solar fuels, etc.. However, CO2 is increasingly beingconsidered a building block rather than a wasteproduct. This changing view is important to theindustry’s medium- to long-term strategy. The steeland cement industry are scouting out technologiesthat could reduce CO2 emissions. Power companiesare showing interest in storing excess (renewable)energy. These industrial players are often acting onthe international level, if not the global level. This

33


means there are good opportunities for the catalysiscommunity to increase interaction with them,capitalizing on the long standing tradition of public-private partnerships within the Dutch school ofcatalysis.

The CO2 conversion topic has many dimensions. Onone end of the spectrum it concerns short-termsolutions to reduce the cost of electrolyzers. On theother end it involves long-term developments suchas the production of chemicals and the developmentof integrated solar-fuel devices. Some of theseaspects are best covered in public-privatepartnerships, in which innovation by SMEs shouldbe strongly supported. The development of a cost-effective and scalable solar-fuels device will requirea considerable long-term effort to overcome themany fundamental challenges. Among other things,considerable investments will be needed toreinforce areas of expertise such as fuel-cellcatalysis, electrochemistry, inorganic chemistry,and theoretical chemistry.

Much of the expertise required to make stepchanges in the field of CO2 conversion and storage

of solar energy is already present in theNetherlands. Catalysis covers a substantial part ofthis expertise but cannot tackle all the challenges byitself. There is a clear need to connect the variousareas of expertise.


Areas of ResearchThere is a great need for a solution regarding thestorage of energy from excess renewable electricityin chemical energy. At this point, the most viablesolution seems to be to use electrolyzers since it isproven technology, although it can only be scaledup if more abundant electrode materials aredeveloped. Renewable hydrogen can then be usedto convert point-source CO2 to fuels. Catalysts forboth these processes need to be optimized to dealwith contaminants present in flue gases and withthe intermittency of renewable energy sources. Thescale at which such operations can be done remainsan important question.

34

Klaas Jan Schouten from the group ofMarc Koper at Leiden University (K.J.P. Schouten et al., J.Am.Chem.Soc.134 (2012) 9864, Angew.Chem.Int.Ed.53 (2014) 10858) discovered that theformation of ethylene from theelectrocatalytic reduction of CO2 andCO is highly sensitive to both thecopper surface structure, with (100)being most suitable surface, and tothe solution pH, with alkalineelectrolyte being the preferredmedium for efficient C-C bondcoupling from CO. These findings havesignificant implications for the designof better electrocatalysts for selectiveCO2 reduction.

Carbon-carbon bond formation on copper electrodes

The development of integratedphotocatalytic/photoelectrochemical devices toproduce H2 is another important area of researchfor the coming decades. The challenge is to developboth cheap materials for photo absorption and newcatalysts and then to integrate those in a devicewith an overall solar-to-hydrogen efficiency of atleast 20% in order to compete withphotovoltaic/electrolyzer technology. This willrequire improved characterization methods forstudying photochemical processes in relation tophotocatalysis as well as new computationalchemistry to deal with specific issues ofphotocatalyst systems. Another type of integrateddevice would have to be developed for storage ofrenewable energy in the form of chemical energy.The development of integrated devices will requirea systems-catalysis approach that includes suchengineering aspects as small-scale and intermittentoperation.

In the long term, the focus will be on highlyintegrated solutions enabling the carbon-neutralproduction of energy in all areas, including mobilityand chemicals. To arrive at this desired situation,technology capable of capturing CO2 from theatmosphere will need to be developed. This mayinvolve artificial leaf approaches, in which CO2from the air is photocatalytically converted intouseful products or intermediates, or approaches inwhich CO2 capture is followed by conversion, eitherelectrochemically or by renewable H2. Biomimeticsas well as genetically modified organisms may alsobe an option. In such a scenario, where humanityno longer depends on fossil resources for energy,these resources (including biomass) could becomethe starting chemicals for the production ofconsumer products. CO2 would no longer be awaste product but would be considered a primarybuilding block. New catalytic processes have to bedeveloped that will allow for an efficient use of CO2as a monomeric unit in the production of fuels andchemicals.


• Scalable electrolyzer technology based on cheapand abundant catalytic metals to convertrenewable electricity into hydrogen;

• A device with a solar-to-hydrogen generationefficiency ≈ 20%, beating the efficiency of PVtechnology;

• Catalytic technologies to store renewableelectricity and/or renewable hydrogen in liquidfuels;

• The integration of solar energy and CO2 use inchemicals and fuels production.

35


Catalytic Synthesis of Bioactive Molecules

As the world has a continual need for a variety

of new bioactive compounds with possible

applications in the food, feed, and health

industries, it is of key importance to be able to

develop new catalytic tools to make the organic

synthesis of bioactive molecules more efficient.

These tools will reduce the related costs and make

synthetic routes more sustainable. This means

that new and improved, environmentally benign

catalysts need to be developed, taking full

advantage of the exciting new tools and methods

being developed in both biocatalysis and

chemocatalysis. These new systems will enable

cost-efficient one-pot cascade reactions and are

expected to give access to a variety of new,

selective synthetic reaction types, allowing the

efficient synthesis of a wide variety of bioactive

molecules.

37


Status & Challenges

Current SituationAs a key enabling science, synthetic chemistryallows the preparation of a wide range of (complex)bioactive molecules. This includes all the vitalmolecules that change our daily lives, e.g.medicines, antibiotics, hormones, vitamins andfungicides, or influence them indirectly, e.g.insecticides, food additives, fertilizers, and toxins. It also includes those molecules that make our livesmore agreeable, e.g. personal-care ingredients,fragrances and flavors. All these molecules are ofhigh relevance for the pharma, agro and health &food sectors. Therefore this is the field where theTop Sector Chemistry has an excellent opportunityto join forces with the Top Sectors Life Science &Health and AgriFood.

Organic chemistry has matured to such anadvanced level that almost any desired moleculecan be synthesized. At the same time, however, thesynthetic chemistry of most bioactive molecules isdominated by stoichiometric chemistry, theabundant use of protection groups, and manyconsecutive reaction steps generally requiringelaborate work-up procedures after each reactionstep. This typically leads to high costs, wasteformation and unnecessary energy consumption.Several examples have illustrated the huge potentialof catalysis in organic synthesis, providing efficientshort-cuts in the overall route. The various cross-coupling reactions (2010 Nobel Prize) and olefinmetathesis reactions (2005 Nobel Prize) usedabundantly in organic synthesis are especiallynoteworthy. The field has made considerableprogress since the last Roadmap for Catalysis, andnumerous catalytic processes have beenimplemented, including C-C bond reactions,hydrogenations, catalytic oxidations, andcarbonylations. Nevertheless, there remains muchroom for improvement. Plenty of stoichiometric

steps still need to be replaced by catalytic processes,for example. Catalysis still offers manyopportunities for synthetic shortcuts.

Elegant and useful chemo-, regio-, diastereo- andenantioselective catalytic reactions have beenintroduced to the field as well, using both synthetichomogeneous catalysts (2001 Nobel Prize) andenzymes. This clearly has boosted the efficiency ofpreparing enantiopure compounds and has led tosubstantially improved selectivities. However, thedevelopment of enantioselective catalysis, amongother selective types, has by no means matured tothe desired level. Many of the known reactions havea limited substrate scope or require thedevelopment of a dedicated catalyst or enzyme.Similarly, the development of one-pot cascade-typecatalytic reactions, using either one catalystmediating several subsequent coupled reactionsteps or a mix of multiple catalysts performingdifferent tasks, is slowly setting the stage. Yet, likeenantioselective catalysis, the development ofcatalytic one-pot reactions is still in its infancy.

ChallengesThe world has a continual need for a variety of newbioactive compounds. Several food-, modern-lifestyle- and aging-related health issues make itimportant to develop new or improved drugs, foodingredients and personal-care-product ingredients.Cities with large populations are in serious dangerof developing untreatable diseases because bacteriaare becoming increasingly resistant to theantibiotics currently available. Furthermore, toproduce enough food for our rapidly growing worldpopulation it is of crucial importance to be able togrow crops in the most efficient manner possible.This, in turn, requires the development of new, safeand bioselective antibiotics, insecticides andfungicides that are harmless to other organismssuch as honeybees, mammals, and birds.

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If we are to meet the challenges presented above,the integration of knowledge and expertise inorganic synthesis, homogeneous catalysis andbiocatalysis is crucial. This needs to be combinedwith efficient reactors, microflow devices andcontinuous-reaction modes rather than with thebatch reactions common in fine chemistry.Furthermore, the field of bioactive molecules ishighly dynamic. Compounds considered relevanttoday may well be outdated next year. Hence thefield needs to be constantly updated withknowledge from hospitals, pharmacy and theagrochemical and food sector including allstakeholders. Furthermore, as the diversity ofcompounds relevant to the medicinal,agrochemical, food and personal-care industries is very broad, it is more appropriate to definetargets in terms of new (selective) catalytic tools forthe synthesis of bioactive organic molecules ratherthan to target a specific molecule. These new toolsshould be as cheap, as fast and as selective aspossible, and they should have a broad substratescope.

Opportunities for CatalysisThere are very many opportunities for catalysiswhen it comes to contributing to the efficientsynthesis of bioactive compounds. Below, we groupthem in two categories: opportunities wherebycatalysis is an enabling tool in synthesis andopportunities whereby catalysis can make synthesismore environmentally friendly and cost efficient.

Catalysis will enable synthesis routes with fewer(but preferably no) protection groups and disclosenew transformations towards the desired productsthat provide synthetic shortcuts, for examplethrough the activation of bonds. Catalytic synthesisis expected to create new reactions for makingcyclic compounds, both heterocyclic and purelycarbocyclic. In biocatalysis, combiningbioinformatics (analysis of the metagenome) withenzyme development should lead to the discoveryand development of new enzyme activities. Usingnon-toxic first-row transition metals as catalysts ormetal-free catalysis will contribute to reducingchemistry’s dependence on scarce elements. Finally,

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Multi-Enzymatic cascade for the redoxneutral isomerisation of allyl alcohols toketones. By combining several enzymesit became possible to reduce one groupwithin one molecule while oxidisinganother. Normally oxidising reagentsand then reducing reagents need to beadded to achieve this, here it is possiblewithout any of these reagents,significantly lowering the environmentalburden of the reaction - and its cost.

Multi-Enzymatic cascade reactions

Reproduced from Inside front cover Chemical Communications Vol.48, Issue 53, with permission of the Royal Society of Chemistry.

catalysis will lead to higher chemo-, regio-,diastereo- and enantioselectivity in chemicaltransformations, preferably with a broad substratescope.

Another important target is the transformation ofstoichiometric reactions into catalytic ones.Mechanistic research will enable the developmentof active and robust catalysts with high turnoverfrequencies (TOF) and turnover numbers (TON),leading to economically viable processes. Improvingon the current situation for one-pot cascadeprocesses is expected to yield more efficientsynthesis requiring less high-energy reagents.Lastly, using immobilized catalysts and enzymeswill enable the development of continuous reactionsrather than batch reactions.

Catalytic methods in complex organic synthesisinvolve either homogeneous or biocatalysis. Thecombined use of (chemo and/or bio) catalystsallows one-pot cascade-type reactions preventingelaborate (waste-generating) work-up proceduresand/or the strict need to protect groups. Important

goals in this field are to develop smart, efficient,short-cut synthetic routes, using cheap and non-toxic catalysts based on first-row transition metals(or even metal-free) catalysts and to developinnovative ways to make such catalysts andbiocatalysts mutually compatible. Interesting newmethods to steer us towards these goals include thefollowing: smart ligand design; screening for newenzymes in the metagenome; making many variantsof one type of enzyme available; modifying enzymesthrough site-selective mutagenesis through directedevolution or rational design or a combinationthereof, i.e. smart libraries and synthetic biology(modifying natural enzymes with chemicalcomponents); compartmentalization; open-shell(radical-type) organometallic catalysis; andsupramolecular approaches in catalysis. All of thisshould contribute to more efficient synthetic routesthat will generate less waste, be less timeconsuming and generally lead to a cheaper andeasier production of bioactive compounds.

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The group of Bas de Bruin (Universityof Amsterdam) developed a newefficient one-pot cobalt-catalyzedprocedure for the synthesis of 2H-chromenes (N. D. Paul, et al., J. Am. Chem. Soc 136 (2014), 1090–1096). These are important structuralmotifs that exist in numerous naturalproducts and medicines, possessinginteresting biological activities.

A Metalloradical Approach to 2H-Chromenes

Dutch Strengths inCatalytic Synthesis ofBioactive Molecules

The Netherlands has traditionally had strongacademic research groups in synthetic(enantioselective) chemistry and catalysis, with acurrent emphasis on catalysis, for example at theUniversity of Amsterdam, University of Groningenand Radboud University Nijmegen. The relativelyfew but nevertheless excellent groups inhomogeneous catalysis and biocatalysis (involved inthe development of new catalysis tools) as well as inorganic synthesis (who apply those tools) form astrong basis for a powerful development in the areaof clean and efficient organic chemistry based oncatalysis. This basis is further strengthened by thecomputational groups that are in part incorporatedin, or linked to, the groups that are developingcatalysts, both in the area of homogeneous catalysisand biocatalysis. The connections with the agro andfood sectors form another strong point in theNetherlands, as those give unusual and fruitfulinput to the catalysis community. Likewise, linking-up with companies that are entering the marketfrom a renewable building-block perspective offersanother opportunity in the field of catalysis forbioactive compounds. This includes vanillin andxylitol from wood (lignin) as well as cholesterollowering ingredients. The catalytic technologyneeded to convert renewable building blocks intouseful chemicals overlaps with the catalysis neededfor bioactive molecules. For example, catalytic esterhydrogenation can be used to reduce highlyoxygenated building blocks, but it is also useful toreplace the stoichiometric (and hence expensive)hydride-reduction technologies currently used inthe fine-chemical sector. Synthesis as an enablingscience for many areas of research is well connectedto catalysis and there is a strong collaborative

network that facilitates new initiatives being takenup and made successful.

The pharmaceutical sector has traditionally been anatural industrial partner of all synthetic groups.With the gradual disappearance of the largerpharmaceutical companies from the Netherlands,new opportunities to take over arise for smaller,more specialized companies such as Synthon,Mercachem or Syncom as well as for new start-ups.The emergence of these new players in thepharmaceutical sector and the companies in theagro and food sectors that are new to the catalyticcommunity might induce changes in the currentway of collaborating in the current PPP-initiatives.Both industry and universities are likely to profitfrom creating a new joint field of overlap.


Areas of ResearchA key problem in the chemical synthesis ofbioactive compounds is inefficiency. The mainproduct obtained is often waste, rather than thedesired compound. Both atom and energy efficiencyare important when it comes to reducing industrialproduction costs and moderating our ecologicalfootprint in a circular economy. To solve theseissues, three strategies have been envisioned.

To enable cost reductions, it is of crucialimportance to develop improved, environmentallybenign catalysts based on abundant metals orenzymes. They should be cheap and safe, allow forcatalyst recycling and lead to high TONs and TOFs.Furthermore, they should also enable new selectivecatalytic synthetic reactions that do not rely onprotection-group chemistry. In chemocatalysis thedevelopment of environmentally benign catalystswill be made possible by utilizing a variety of bio-

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inspired tools based on both “cooperative” and“redox-active” ligands. A transition from the use ofrare and noble metals to abundant and cheap, first-row transition metal catalysts is typically associatedwith a switch to entirely different (radical-type)reaction mechanisms. Selective radical-typeprocesses are certainly possible in the coordinationsphere of transition metals, as a variety of highlyselective enzymatic radical-type processes havedemonstrated. Equally selective radical-typeprocesses will be developed with syntheticchemocatalysts. Mechanistic research is crucial ifwe are to arrive at the desired catalystimprovements and cost reductions. Understandingthe behavior and reactivity of metallo-radicals andmetal-bound “substrate radicals” during catalyticturnover is crucial. This applies both to thedevelopment of catalysis with abundant metals andto uncover new, selective (one-pot, cascade-type)radical-type reactions such as C-H bondfunctionalization and catalytic radical-type ring-closure reactions without the need for usingprotection-group strategies. Besides catalystactivation, also catalyst deactivation pathwaysshould be studied, as deactivation is frequently animportant reason for low total TONs and decreasingTOFs over time. Biocatalysis is of course theobvious alternative approach if we are to developenvironmentally benign catalysts. In biocatalysis,major steps forward will be made, extending thecurrently limited spectrum of enzymes by tappinginto the vast number of the biosynthetic enzymesthat nature utilizes for the synthesis of verycomplex structures. By way of metagenomics andsequencing, this toolbox is now coming into reach.Progress towards this goal further assisted by thefast robotic synthesis of DNA, making all enzymesessentially commercially available, scalable andthus affordable.

Cost-efficient one-pot cascade-type reactions will bedeveloped based on sustainable starting materialsreplacing step-by-step syntheses with many

purification sequences. To enable this, catalystimmobilization, compartmentalization of catalysts(e.g. in MOFs or supramolecular capsules) and flowsystems for cascades will be studied. The results will be drastically shortened synthesisroutes. When several enzymes that do not belong to one natural route are combined and co-expressedin one organism, the cascade can be realizedimmobilized inside cells. Combining enzymecatalysis with chemocatalysis offers further excitingprospects. This also holds for the combination ofchemo- and biocatalysis with fermentation. Inparticular, the synthesis of non-natural antibioticsin combined approaches is very valuable and tosome extent already a reality.

The abovementioned new and improved catalystsshould enable a variety of new, selective syntheticreaction types that are catalytic and do not requireprotection-group chemistry. Challenging new C-Cbond formation strategies, (radical-type) ring-closing reactions and C-H bond functionalizationstrategies will be developed. Additionally, thereplacement of C=O by carbene precursors,isonitriles and other building blocks will beinvestigated, aiming for the development of new,generally applicable synthetic methodologies. The currently very polluting amide synthesis as wellas heterocyclic chemistry will be converted intocatalytic chemistry based on biocatalysts andhomogeneous catalysts. In particular, nitrogencontaining heterocycles and complex (hetero)cycliccompounds demand new catalytic approaches thatcan be of an equally revolutionary power as cross-coupling reactions. New homogeneous catalysts willbe developed and biocatalysis will be expandedfrom degrading enzymes to synthetic enzymes. Thisapproach has been developed in part for peptidesynthesis, but the scope needs to be broadened to a variety of other amides.

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Development of improved orenvironmentally benign catalysts• Catalysts based on readily available metals and

ligands;• Mutually compatible chemo- and biocatalysts;• Mechanistic insights that enable the desired

catalyst improvements (cheap and safe metals,catalyst recycling and increasing TONs and TOFs)and, hence, cost reductions;

• Reduction, recycling and replacement of keybuilding blocks for catalysis (e.g. P-ligands);

• Biocatalysis readily available as a standard tool.

Cost-efficient one-pot, cascade-typereactions• Efficient synthetic catalytic shortcuts;• Of-the-shelf ordering of tailor-made and designed

enzymes;• Application of new catalytic methods in

commercial processes; • Better catalyst recovery methods (Late transition

metal catalyst);• Continuous reactions for enzymes and

homogeneous catalysts.

New, selective synthetic reaction types • Transition from stoichiometric chemistry to

catalytic chemistry;• New methods to run cascades from low-energy

starting materials;• New catalytic processes with new (bio)catalysts

running with low catalyst loading and achievinghigh TOF and TON values;

• New reactions towards polycyclic and heterocycliccompounds;

• Development of entirely new catalytic reactions tofacilitate (chemo-, regio-, diastereo- andenantioselective) organic synthesis.

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Precision Synthesis of Functional Materials

A major inroad into innovation for polymeric

materials will be the design and catalytic synthesis

of functional polymeric materials displaying

targeted properties. This involves both the bulk as

well as the surface of the material. Precision

catalysis with novel methodologies can play an

important role in polymerization, cross-linking,

degradation and (post-polymerization) surface

modification. It is applied to influence the

chemical nature of the material as well as the

temporal and topological aspects of its function.

The increased introduction of catalytic concepts

within materials-surface science may lead to

important breakthroughs in the manufacturing of

functional polymeric and hybrid materials.

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Catalysis – Key to a Sustainable Future | Precision Synthesis of Functional Materials

Status & Challenges

Current SituationIn synthesizing functional materials, one aims tocontrol the properties and functionality of the bulkmaterial or its surface. This includes controlling itsidentity (chemical nature), as well as certaintemporal (order of events) and topological aspects(position, micro-meso-macro length scales).Catalysis plays an important role in polymerization,cross-linking, degradation, and (post-polymerization) surface modification. As such,tailor-made (high) performance polymers andcomposites were included in the previous CatalysisRoadmap as a goal. However, this did not result in alarge research effort at the time. Novel catalyticmethods might improve material performance, butthey could also help to improve processability or tolower the ecological footprint in various ways. Inthis way, catalysis also contributes to meetincreasingly strict Health, Safety, Environment(HSE) regulatory constraints. Examples includemore sustainable and safer production methods,lower production cost, lower energy consumption inthe production process or by the customer, andcontrol over service life-time, recyclability anddegradation. These are all –technological- aspectsof a circular economy. The production of suchsmart materials is one of the ambitions of the TopSector Chemistry. There is ample opportunity forintegration with the Top Sector High Tech Systemsand Materials (HTSM), as the application of thesesmart materials is key in this Top Sector.

A limited number of polymerization technologiescurrently prevail, viz. Ziegler-Natta catalysis forpolyolefins and polycondensation for engineeringplastics and coatings (polyesters, polyamides,polysiloxanes). Other technologies comprise(controlled) radical polymerizations (in particularReversible Addition-Fragmentation chain Transferor RAFT) and cobalt-catalyzed oxidative curing, but

also other types of curing catalysis like thevulcanization of rubber or curing catalysis as a toolto enable the self-healing of materials. Novelcatalytic polymerization tools are being added tothe toolbox, e.g. metathesis, “C1” (carbene)polymerization, copolymerization of alkenes withother monomers such as CO, carbene precursors,epoxides, aziridines, cyclopropanes, cyclopropenes,alkynes, polar vinyl monomers and enzymaticpolymerization.

ChallengesDespite its huge industrial importance, polyolefin(PO) catalysis mostly uses a heterogeneous Ziegler-Natta catalyst that is still poorly understood.Increasing our level of understanding of this type ofheterogeneous catalysts is highly desirable as thatwould allow better fine-tuning and control of thepolymer properties. In general, the challenge incatalytic technologies for PO synthesis is the controlof the product microstructure by a suitable catalyst.This includes the use of block copolymerization, thecontrol of bimodality, and the inclusion of a polarfunctionality in the product material, which forexample could render the material oil-resistant orlead to improved adhesion. To that end,polymerization catalysts are needed, includingthose that allow block copolymerization and thosethat accept monomers functionalized withheteroatoms. Such monomers may go beyondolefinic monomers. From a long-term perspective,the shale gas revolution challenges the economicviability of traditional PO feedstocks and mayprompt us to consider methane as an earth-abundant hydrocarbon not currently considered asa monomer to access polyolefins. With vinylmonomers instead of simple olefin monomers, theaforementioned needs can be (partly) met bycontrolled radical polymerization, which, asexemplified by RAFT, is characterized by a broadfunctional group tolerance. Still, this RAFTapproach faces challenges related to the cost andlarge-scale availability of the required control

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agents, color and/or malodor generated bysulfurous RAFT agents, color and/or toxicity as wellas to the lack of functional group tolerance oftransition metal-based agents.

Polycondensation catalysis for polyesters,polyamides, and polysiloxanes is still a largelyunexplored territory for the catalysis community.The catalytic reactions form a complex kineticnetwork with poorly understood multiple equilibria.So far, we have little control over undesired trans-esterification or amidation, we have little controlover molecular weight/distribution, and we havelittle control over chemoselectivity (e.g. thedistinction between aryl and alkyl monomers).There is also a need for methods that will allowselective end-group functionalization withoutbreaking the polymer chain. Gaining control ofthese aspects would mean getting closer to trueprecision synthesis. Another challenge concerns the

development of lower-temperature technology,which is desirable for reasons of life-cycle-assessment (LCA) impact, atom efficiency,selectivity control, and the extra opportunities forthe use of thermolabile monomers. HSE regulationmight prompt us to look for low-toxicity substitutesfor the current tin catalysts, as well as for catalytictechnologies to recycle these materials. Thedevelopment of “restriction catalysts” that wouldcut the bond between specific monomers analogousto enzymatic degradation is an interesting optionhere.

There are also various challenges arising from(autoxidative) curing and vulcanization asapplication areas. Here, too, HSE regulations putpressure on the development of substitutes for thewidely applied cobalt catalysts for autoxidativecuring of alkyd resins. The development of efficientreversible rubber-vulcanization technologies

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Hage, Gibbs and co-workers publishedan overview of paint drying catalysts(J.W. de Boer, et al, Eur. J. Inorg. Chem.,2013, 3581). Alkyd-based paints needcatalysts for oxidative curing. Due to aprobable classification of the widely usedcobalt carboxylates, the coatings industryis seeking alternative oxidative dryingcatalysts. Various manganese and ironpaint driers containing polydentateligands show good paint drying activity.The most active manganese and ironcatalysts were previously identified asstain bleaching catalysts in detergents,and are effective for alkyd paint curingvia similar mechanisms as thoseexhibited for oily food stain bleaching.

The quest for cobalt-free alkyd paint driers: ironand manganese based alkyd paint drying catalysts

presents another challenge that addresses theincreasing need for efficient recycling technologies.Catalysis is generally expected to contribute to thedevelopment of polymers that can reversibly bedepolymerized and triggered (bio)degradation,addressing environmental problems (e.g. “plasticsoup”). Another challenging area concerns theresearch and development of latent catalysts thatbecome active in curing or self-healing on demandand can be included within the product.

Finally, there are also various challenges arisingfrom the limitations of the technologies that arecurrently employed in the post-polymerizationsurface modification of materials. The most widelyused method, i.e. plasma treatment, requiresspecialized, dedicated equipment, is very aggressiveand unselective, and suffers from a lack oftopological control. A key requirement is that thebulk properties of the polymeric material not besignificantly altered, e.g. by undesired chain-breaking reactions. Evidently, especially the surfacemodification of polyolefins presents a verychallenging task, given the very unreactive nature ofthe aliphatic methylene groups.

Opportunities for CatalysisAn attractive opportunity would entail integratingthe current catalytic approaches to the precisionsynthesis of functional materials with processintensification, biocatalysis, and traditionalpolymer science. A number of ongoing projects inthe Dutch Polymer Institute (DPI) deal withpolymerization catalysis or offer opportunities forincluding this. More specifically, this integrationincludes catalysis for polyolefins, performancepolymers, functional polymers (e.g. responsivematerials), and coatings of various sorts (e.g.daylight photo-initiated curing systems or drug-releasing biomedical coatings).

The use of renewable feedstocks should beincorporated here. Catalysis not only plays a crucial

role in the generation and further conversion ofmonomers from carbohydrates as feedstock, butalso in the valorization of other plant-derivedfeedstock streams. Successful valorization of allstreams is a prerequisite for success in biomaterials.In this respect, the most recalcitrant streams at themoment are lignin and humins, see also thechallenges presented in Chapter 4. These streamsare expected to serve as feedstock for biobasedthermoset resins, e.g. as substitutes forphenol/formaldehyde resins.

Biocatalysis for material-science applications is an active and fast-growing field of research.Significant progress has been achieved in this area,not only with respect to enzymatic polymerizationcatalysis, but also with respect to enzymatic surfacemodification. New biocatalytic polycondensationtechnologies appear particularly well suited to deal with thermolabile monomers. Currentcommercially applied polymerization technologiesare dominated by chemocatalysis.

For catalytic surface modification, research onchemocatalytic approaches strongly lags behindenzyme catalysis. There are clear opportunities forboth bio- and chemocatalysis in this area, withstrong synergism arising from exchanging reactivityconcepts. Recent approaches in homogenouscatalysis such as ligand-assisted catalysis or outer-sphere catalysis should be explored as leads for newconcepts in catalyst design. This approach oflearning from other disciplines can be extended toinclude biocatalytic enzyme design rules withrespect to primary, secondary, tertiary, and/orquaternary structure. This way of thinking may leadto solutions for longstanding problems inpolycondensation technology such aschemoselectivity control by monomer distinctionand selective end-group functionalization withoutchain breaking. Clear opportunities also arise fromthe need to achieve improved control of materialproperties by a better understanding of the various

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types of commercially relevant heterogeneouspolymerization catalysts, such as Ziegler-Natta andsiloxane polycondensation catalysts. An interestingapproach with many opportunities towardsimproved materials is the development of hybridmaterials made of polyolefins and engineeringplastics. To achieve formation of such hybridpolymers, the integration of multiple catalyticcycles is required. The development of aheterogeneous block-copolymerization catalyst isalso of great interest in order to achieve bettercontrol of material properties. Blockcopolymerization in general offers manyopportunities to improve the current situation.Organocatalytic approaches appear to be ofparticular interest, given the increasing pressureimposed by HSE regulations to avoid toxic metals.Single-Electron Transfer Living RadicalPolymerization (SET-LRP) is one of the moreinteresting new developments with potential tomeet industrial demands given the sub-ppm levelcatalyst loadings.

The development of efficient polycondensation orcuring catalysts based on non-toxic, earth-abundantmetals as substitutes for the above-mentioned tinand cobalt catalysts presents another opportunityfor chemocatalysis. Obviously, bio- ororganocatalysis may also offer solutions that areacceptable from an HSE point of view. Thetransition towards biobased monomer production(e.g. from fermentation) offers an opportunity torethink the traditional process routes. If, as in thecase of polycondensates, monomers need to beactivated before polymerization, they could beactivated directly through an appropriate catalyticprocess. This would require the integration ofmultiple catalytic cycles, see also the research areasparagraph in Chapter 8 Integrated Multi-CatalystMulti-Reactor Systems. Integration of bio- andchemocatalytic cycles may require development of enzymes that operate efficiently in media thatallow sufficient solubility of the polymeric material.

Taking it yet another step further would meanconsidering the design of new polymer systems as well.

Dutch Strengths inPrecision Synthesis ofFunctional MaterialsResearch and production of functional materialswill remain present in developed countries such asthe Netherlands despite the trend of shifting theproduction of polyolefins to countries with lowenergy prices and easy access to raw materials.There is no trend of relocating the production ofcoatings and paints to low-cost countries, sincethese are always produced locally for economicreasons.

Academic studies on PO catalysis focus mainly onwell-defined single-site metallocene homogeneouscatalysts, rather than on the multiple-siteheterogeneous Ziegler-Natta catalysts that are usedin industry. In the Netherlands, a number of well-respected academic groups in this latter area havebeen discontinued. Many of the catalysis-relatedproblems within polycondensation of polyesters,polyamides, and polysiloxanes have nottraditionally been part of the research areasaddressed by the Dutch catalysis community. As a result, crucial expertise in and knowledge of bothPO and polycondensation catalysis is currentlyprimarily present in Dutch industrial laboratories.For polyolefins these are for example Dow, Sabic,Lanxess, and DSM, and for polycondensationAkzoNobel, DSM, and Avantium should bementioned. However, there is sufficient knowledgeof and expertise in homogeneous catalysis,heterogeneous catalysis and biocatalysis availablein the Dutch academia to meet industrialchallenges. Establishing novel collaborations

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between these two communities is the key tosuccess in this regard, e.g. via matchmakingactivities leading to joint research projects.Research on materials from renewable feedstocksclearly demonstrates that this approach issuccessful and is leading to research areas of jointinterest to both academia and industry, asexemplified by various existing (e.g. CatchBio) andnew (e.g. InSciTe) PPPs. The growing importanceand strength of the biobased materials area withinthe Netherlands is illustrated by various Dutchcompanies active in the field, such as Avantium(FDCA), DSM (succinic acid), BiChem (isosorbide),and Corbion (lactic acid). Catalysis research forfunctional materials may also benefit from Dutchacademic and industrial expertise on radicalpolymerization and supramolecular chemistry, notonly in terms of designing new materials withimproved properties, but also in terms of designingnew catalysts to address challenges such aschemoselective polycondensation or end-groupmodification.

Research Areas &DeliverablesAreas of ResearchThe challenges stated in the foregoing sections callfor the following two research approaches. Firstly,we should aim for a better understanding and bettercontrol of the properties of polymers resulting fromeither PO or polycondensation catalysis. Examples ofwhat this understanding and control would lead toare a better defined molecular weight (distribution),chemoselective polymerizations, selective end-groupfunctionalization, the incorporation of polarmonomers and block copolymerization. Most likelyresearch into new or modified catalysts for thesereactions will be included. A specific area of catalystdevelopment is formed by the latent, “on-demand”polymerization catalysts for curing or self-healing.Finally, we highlight post-polymerization surfacemodification through bio- or chemocatalysis here as a less conventional way to engineer polymerproperties.

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Rob Jacobs and Rint Sijbesma (TUe) developedlatent metathesis catalyst with polymer chainsattached to the ligands (R. T. M. Jakobs et al.,ACS Macro Lett., 2013, 613–616). Mechanicaldeformation of a polymeric material removes oneof the ligands from the ruthenium center and thusactivates the embedded catalyst for the ringopening polymerization of norbornene. Theresponsive material demonstrates a promisingnew approach to self-healing materials.

Reprinted (adapted) with permission from R.T.M. Jacobs et al., ACS Macro Lett. 2013, 613-616. Copyright 2013, AmericanChemical Society.

Mechanically induced activation of a polymerizationreaction

Secondly, alternative polymerization technologiesshould be explored. These would include controlledradical polymerization technologies (e.g. RAFT andSET-LRP) with low-cost, universal applicability andexcellent functional group tolerance without toxicity,odor and/or color issues. Also new (advanced)polymerization technologies based on newmonomers, including non-olefinic monomers suchas carbene precursors, epoxides and aziridines, aswell as methane as an earth-abundant, non-traditional monomer, should be mentioned here. A particular alternative technology is formed by theintegration of multiple catalytic cycles that enableformation of hybrid materials made of polyolefinsand engineering plastics.

In both of these research areas, we have to keep inmind the increasingly strict LCA and HSErequirements. These requirements do not lead to adistinctive research area in itself but may be adriver towards low-temperature PO orpolycondensation technologies. Also more attentionfor the recyclability of polymers (e.g. via reversiblerubber-vulcanization technologies), materials andpolymerization technologies based on renewablemonomers, and catalysts based on earth-abundant,non-toxic metals, biocatalysts, or organocatalysts.

Deliverables in 10-20 yearsThe ultimate goal in polymerization catalysis is toallow any set of monomers to be polymerized in acontrolled manner in any desired order to achievethe desired properties of the material while meetingall application, HSE, and LCA requirements.Deliverables that are more realistic given the time-span of 10-20 years are outlined below. In all cases,“industrial applicability” is an importantcomponent of the deliverables that is not specifiedseparately.

• A tunable, heterogeneous polymerization or blockco-polymerization catalyst for both simple andpolar olefins;

• An integrated catalytic system based on multiplecycles for the formation of hybrid materials madeof polyolefins and engineering plastics;

• Polycondensation catalysts that meet HSErequirements and are selective with respect to thecontrol of molecular weight (distribution) anddistinct monomer reactivity;

• Curing catalysts that meet HSE requirements;

• Catalytic technology for post-polymerizationcontrol of material properties: selective end-group functionalization without chain breaking,surface modification of polymers as a substitutefor plasma treatment;

• Controlled (radical) polymerization technologiesfor polymerization and block copolymerization,also of highly functionalized monomers;

• Low-carbon-footprint technologies: low-temperature polycondensations, recycling viaeasily depolymerizable polymers (e.g. viareversible rubber vulcanization), materials basedon renewable monomers;

• Latent, “on-demand” polymerization catalysts forcuring or self-healing;

• Polymerization technologies for (advanced) newand drop-in materials based on non-conventionalmonomers, e.g. epoxides, aziridines, but alsomethane as earth-abundant, non-traditionalmonomer.

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Catalysis – Key to a Sustainable Future | Integrated Multi-Catalyst Multi-Reactor Systems

Biology provides compelling demonstrations of what

may be achieved by the integration of many different

catalysts into a single system. The development of

synthetic multi-catalyst (multi-reactor) systems has

been identified as one new strategic direction in

which the Netherlands has a combination of strengths

that is unique in the world. Two complementary

approaches have been identified: The first aims at

improving the efficiency with which chemicals are

produced by integrating modular catalytic systems in

a plug-and-play fashion within a flow system (also

known as the “LEGO” approach). The second

approach aims at the integration of multiple catalysts

in a single environment in which catalytic processes

influence each other through multiple feedback loops,

with the ultimate aim of synthesizing life de-novo and

producing a synthetic cell. Both approaches touch on

the concept of molecular complexity, in which control

over different length scales and timescales is crucial.

Integrated Multi-Catalyst Multi-Reactor Systems

Status & Challenges

Current SituationIntegrating multiple catalytic reactions into a singlesystem is an important challenge across the fields ofhomogeneous catalysis and biocatalysis. Integrationcan improve the efficiency of catalytic processes aswell as lead to entirely new functions. Biologyprovides many compelling examples ofsophisticated functions that emerge as the result ofcombining different catalytic processes. The fieldsof synthetic biology and biotechnology utilize a top-down approach, modifying existing biologicalsystems to engineer new functions. These can rangefrom the production of a specific chemical tosystems capable of computing based on chemicalinputs. The bottom-up approach to complexcatalytic systems is currently underdeveloped andconstitutes an important direction for futureresearch. Man-made catalytic systems are free fromthe restrictions inherent to biology, permitting theuse of a wider range of experimental conditions andallowing the targeting of a wider range of functions.At the same time, engineering complex catalyticsystems will deliver new fundamental insights andis likely to lead to the discovery of new andinherently unpredictable emergent functions.

The majority of synthetic catalytic systems inhomogeneous catalysis and biocatalysis operatewith only one reaction, only one catalyst and onlyone reactor. There is a recent trend towardscombining multiple catalysts within a single systemor device: the so-called catalytic cascade or dominoreaction. In the bulk (petro)chemical industry theaspect of process intensification by combiningmultiple catalytic functions is already much furtheradvanced and several processes operate based onmultiple catalysts arranged in a stacked bed.Another important example of a multi-catalystdevice in heterogeneous catalysis is the use ofspatially and temporally separated reduction

catalysts and NOx-trap catalysts in car exhaustsystems. In the previous Roadmap, “integration”was one of the keywords. However, this mostlyreferred to integration of reaction and processdesign in bulk chemistry. While the chemicaldevelopment of multi-catalyst systems inhomogeneous and biocatalysis is already underway,the engineering counterpart, (i.e. multi-reaction ormulti-reactor systems) is lagging behind. That isunfortunate, as such systems would offer attractiveopportunities in process intensification.

The integration of catalysts can be achieved usingtwo different approaches. The first is the plug-and-play or “LEGO” approach, whereby individualcatalytic systems are self-contained and modular,but nevertheless combined with other catalyticmodules. Simple implementations of this conceptare already being applied industrially, for exampleby coupling a first equilibrium reaction to a secondirreversible process, which drives the firstequilibrium reaction to completion. Another areathat requires the integration of catalysts is thedevelopment of solar fuels, where oxidation andreduction occur concurrently, but need to bespatially separated, see also the challenges andopportunities paragraphs in Chapter 5 CO2Conversion and Solar Energy Storage. The overallgoals of the plug-and-play approach are to expandthe repertoire of viable chemical reactions, toincrease product yield and selectivity, and to reducethe production of waste, thus enabling processintensification and increasing cost-effectiveness.

The second approach, which we will call the bio-inspired approach, is more reminiscent of howcatalysis occurs in biology. There catalytic systemsco-exist and influence each other, for examplethrough feedback loops. The highly ambitious long-term goals in this approach are to build a syntheticcell and create life de-novo. This approachresonates with complexity research as it isconducted in and across many different disciplines,

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including topics ranging from social networks to theresearch on the brain. So far, within the field ofcatalysis, complexity research remainsunderdeveloped, although momentum is gathering.

ChallengesThe main challenges that need to be addressed inorder to make more complex catalytic systems areality are catalyst and process compatibility. Asingle synthetic catalyst is usually only effectiveunder its own set of special experimental conditionsand usually has limited tolerance for other chemicalspecies in the system. Yet, building more complexsystems or devices requires compatibility – ideallybetween different catalysts, but at least betweenconditions and/or process parameters.

For the “LEGO” approach there is a need for plug-and-play catalytic modules, whether as units thatcan be combined within the same homogeneousenvironment or separated by compartmentalizationor immobilized in (micro) flow reactors. Systemsmay require structured reactors, in which reactorsand catalysts are ideally optimized simultaneously,requiring close collaboration between chemists andengineers. It will also be important to develop andincorporate inline analytical technologies (ultra-sound tomography, temperature tomography,NMR, etc.) into the reactors to be able to study (inthe development phase) and monitor (in theproduction phase) the processes. A cascaded flowprocessing needs also to ensure that solvents,concentrations, ingredients, etc. are compatiblewith each other in what is referred to as “floworthogonality”. Another major challenge resultsfrom differences in the rates at which catalysts losetheir activity, usually through poisoning orleaching. A workable integrated multi-catalystsystem will therefore have to offer the opportunityof independent catalyst-activity management.

For the bio-inspired approach, the main challengeis to achieve good compatibility between the manydifferent catalytic sub-processes that occur inparallel in a single system. Nature’s solutions for avoiding unproductive interference betweensub-processes is to separate them in space byimmobilization, compartmentalization or stericshielding. Most catalytic sites in enzymes are insidecavities in the structure of the enzyme, while inmost man-made catalysts, the catalytic sites tend tobe exposed. Work has started on implementingsimilar immobilization strategies with man-madecatalytic systems.

Opportunities for CatalysisWhen combining chemical processes side-by-side(as in the “LEGO” approach) or within a singlesystem (as in the bio-inspired approach), catalysisis essential as it allows independent control over therates at which the various reactions occur. Suchcontrol is crucial if the various reactions are to beefficiently integrated. Without catalysis, suchcontrol is largely absent and one would bedependent on the rate constants of the variousreactions. That, in turn, would severely restrict theability to engineer well-integrated complexchemical systems. For example, a cell would not beable to function in the absence of ways toindependently regulate – through catalyticprocesses – the rate at which the various chemicalreactions inside it occur. Thus, by developingintegrated catalytic systems, we will be opening upnew opportunities, ranging from a more cost-efficient production of chemicals that requiremultiple reaction steps to functional complexchemical systems leading to life de-novo and cellsthat are completely synthetic.

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Dutch Strengths inIntegrated Multi-Catalyst Multi-ReactorSystemsThe integration of multi-catalyst systems and theaccompanying processes requires the integration ofthe underlying disciplines such as catalysis,chemistry, process engineering, biology and physicsand it requires the integration of the communitiesthat work in these disciplines. Through its nationalprograms and events the Dutch school of catalysishas a long and unique tradition when it comes tointegrating homogeneous catalysis, heterogeneouscatalysis and biocatalysis with biotechnologyresearch. Such integration at the level ofcommunities will benefit a similar integration at the level of the actual catalysts. The Netherlands isalso strong in bridging chemistry with chemicalengineering and vice versa, e.g. the chemical and/or biochemical technology departments at thetechnological universities. A holistic approach isultimately needed to bring innovations into practiceand to ensure industrial valorization. Process-design and engineering departments such as thoseat the universities of Delft, Twente, and Eindhovenwill play a crucial role in the end-of-the-pipeimplementation, particularly for the “LEGO”approach.

Furthermore, academia in the Netherlands hasinternationally leading expertise in the area ofcomplex chemical systems, e.g. in the Gravityprograms on Functional Molecular Systems and on Multiscale Catalytic Energy Conversion, in theresearch initiatives in Groningen, Nijmegen andEindhoven, and through its leading role inconsecutive COST Actions on Systems Chemistry.The development of complex catalytic systems will benefit from combining the strength of thesupramolecular and catalysis communities. The

first steps in this direction have already been takenin the context of the NRSCC. In the meantime,however, that program has come to an end, and wehave to ensure that the momentum that had beenbuilding will be passed on to the new initiatives.

Another impetus for research on integratedcatalytic systems comes from the “cell as a factory”research within BE-Basic. Finally, large chemicalcompanies such as DSM often have highlydeveloped competences in individual technologiessuch as homogeneous catalysis, heterogeneouscatalysis and biocatalysis and flow chemistry, and a combination of these competences is wheredifferentiation from competitors kicks in.


Areas of ResearchThe application of multi-catalyst systems and therespective multi-reaction/reactor systems rangesfrom a relatively straightforward extension ofexisting methodology, whereby the resulting systemhas properties that are effectively a sum of itsindividual components, to systems which showemergent behavior. In the latter case the total ismore than the sum of its parts, and a collection ofcatalysts create a function at a higher level. We candistinguish between the plug-and-play or “LEGO”approach and the bio-inspired approach and definespecific research areas. For the plug-and-playapproach these lines include serial multi-stepreactions in a flow setup (serial multi-devicereactions) leading to specific products. Theimplementation of such systems requirescontrollable plug-and-play devices in whichcatalyzed reactions may be performed. Catalystactivity is independently managed for each device.The product of a single step, which is the substratefor the next step, is selectively and continuously

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removed from the device and fed into the next unit.The development of such systems requires the inputfrom separation technology, organic chemistry andprocess technology.

Two research lines may be implemented that useeither the “LEGO” or the bio-inspired approach.The first line includes one-pot multi-step chemicaltransformations involving multiple catalysts leadingto specific products. The second line involves smartcatalytic systems in which the outcome (i.e. productselectivity) may be controlled by controlling theindividual reaction steps or in which the activitymay be controlled in time and/or space through(local) physical or chemical triggers. This requiresthe development of stimuli-responsive catalysts.The possibility of having dynamic variation ofcatalyst activity, e.g. by electronic control, may beanother asset. The industrial implementation ofsuch systems requires analytical methods that are

sufficiently fast and specific to fit their processcontrol task. This adds analytical science to therequired competencies.

For the bio-inspired approach to integration, a specific area of research is formed by networks of catalyzed reactions that are stronglyinterconnected and that give rise to emergentfunctions as they would do in biology. Here it is not necessarily the product of the reaction networkbut rather its functional behavior that is of interest. Such functions may include computation,autocatalysis/self-replication, oscillations, andspatio-temporal pattern formation (Turingpatterns). The ultimate aim for many researchers inthis field is to create life de-novo. Feedback loopsare essential elements for advanced function anddesigning and engineering catalytic systems thatinclude feedback loops is of prime importance.Internal control mechanisms in such systems will

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Jan van Hest and coworkers (Peters, R.J.R.W.et al., Angew. Chem. Int. Ed., 2014, 53, 146-150) used polymeric vesicles to recreate thestructural design of a eukaryotic cell and itsorganelles. Such multicompartment structurescan be made by encapsulating small porouspolymeric nanoreactors inside a larger

polymeric vesicle. This system can then beused to spatially separate incompatibleenzymes from each other by positioning themin different organelle subcompartments. Thisstill allows the enzymes to function togetherin a multi-step cascade reaction, but withoutaffecting the other catalysts.

First artificial cell with working organelle

Figure reproduced in adaptedform from Peters et al.,Angew. Chem. Int. Ed., 2014,53, 146-150, with permissionof John Wiley and Sons.

rely heavily on non-covalent interactions, whichmeans it will be important to involve the strongsupramolecular chemistry community in theNetherlands in the development of this line ofresearch.


Plug-and-play (“LEGO”) approach• a toolbox of plug-and-play catalytic modules in

which catalysts are integrated into tailoredreactors;

• several industrial (flow) processes in whichmultiple catalysts are integrated which enabled amore cost-effective production of (fine)chemicals.

Bio-inspired approach• the ability to design and synthesize integrated

catalytic systems exhibiting feedback behavior;• significant steps towards the synthesis of life de-

novo, in particular fully synthetic self-reproducing catalytic systems will have beenmade that are capable of undergoing Darwinianevolution. While the synthesis of life de-novo mayrequire several decades, significant steps towardsthis tantalizing goal will have been made towardsthe end of the period covered by this Roadmap;

• man-made integrated multi-catalyst systems thatcomplement current biotechnology-basedprocesses in the production of fine chemicals.These industrial applications are appearing onthe horizon, although those may well lie beyondthe timescale of the present Roadmap;

• personalized medicine, where micro or nanoscaleintegrated systems autonomously perform in-vivosensing, data analysis and treatment by release ofspecific drugs.

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The future development of new and improved

catalytic material and processes will require a

methodological shift towards rational design

supported by fundamental knowledge. The

integration of new spectroscopic and microscopic

tools along with predictive modeling strategies

will allow us to design and synthesize new

molecules and complex materials with structural

and chemical properties that are well-defined and

controlled over various length- and timescales,

leading to more cost-effective and sustainable

catalysts and catalytic processes. Improved

fundamental knowledge of catalysts (and catalysis

in general), including their functioning and

manufacturing processes, will enable, among

other advances, the replacement of noble, scarce,

and toxic elements by more abundant and

environmentally safe metals for catalysis.

Fundamentals and Methodology 61

Catalysis – Key to a Sustainable Future | Fundamentals and Methodology

Status & Challenges

Current SituationIn the last decades, technological developments in the fields of spectroscopy, imaging andcomputational tools have provided increasinglydetailed molecular insight into catalytic reactions,including examples of atomic descriptions of catalyticprocesses, making it possible to explain the reactivityobserved. Despite these advances, a complete spatialand temporal description of such events is not yetpossible, and new technological breakthroughs arenecessary before we can observe the full “movie” of catalysts in action – a challenge for bothhomogeneous and heterogeneous catalysts. A newscientific and technological revolution, characterizedby cost-efficient and smart chemical systems, willrequire a transition from explaining to predictingmaterial-design parameters for new catalysts.

In relation to the 2001 Technology Roadmap, thesubject of fundamentals and methodology wasmostly examined in the ASPECT- and CatchBio-programs, in which a variety of new spectroscopic

tools were developed. This new Roadmap focuseson introducing predictive power into catalysis andcenters on the development of new experimentaltools and theoretical methodologies that will lead tothe knowledge-based design of any desired catalyticsystem. The rational design of catalysts hashistorically required the study of well-definedsystems to allow changes in performance to becorrelated to a small set of material parameters (inheterogeneous catalysts) and molecular structure(in homogeneous catalysts). Although tremendousprogress has been made in closing the gap betweenmodels and realistic systems, further studiescombining theory, spectroscopy, and synthesis willbe required to fully bridge this gap. This holds truefor all types of catalysis. The guiding principle forthe fundamental direction will be the combinationof predictive molecular modeling, advancedmolecular gas- and solution-phase spectroscopy, 3Datomic-resolution spectroscopy, and the capabilityto translate the lessons learned into the design andsynthesis of catalysts and catalytic processesranging from the atomic and molecular levels tomacroscopic scales.

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Ines D. Gonzalez-Jimenez, working with Profs.Frank de Groot and Bert Weckhuysen, provedthat individual iron-based Fischer–Tropsch-to-Olefins (FTO) catalyst particles can be studied byIn-situ Hard X-ray Nanotomography at elevatedtemperatures and pressures. 3D and 2D maps of30 nm resolution could be obtained and showheterogeneities in the chemical composition andpore structure of the catalyst particle of about20µm. (Angewandte Chemie InternationalEdition, vol 51, 11986–11990, 2012).

Nanotomography of working catalyst particles

ChallengesHaving a fundamental understanding of catalyticprocesses on multiple timescales and length scalesis key to identifying and overcoming the majorbottlenecks to scientific and technologicaldevelopments. A continuous drive to bring aboutimprovements in the stability, selectivity andperformance of catalytic systems, from laboratoryto industrial levels, must therefore be supported bystrong research efforts in fundamental research andin the development of novel methodologies. In thisconnection, we list six important challenges forfundamental research in catalysis.

Advances in catalysis, be it homogeneous,heterogeneous or biological, will require optimalcontrol over chemical reactions (i.e. chemicalbonds), catalytic sites in molecular catalysts, andsurface structures. We need to fundamentallyimprove our understanding of catalysis, andimprove our capability to selectively activate thedesired bonds. Equally so, spectroscopy at the levelof the single molecule or the single catalyst site willhelp us better understand the effects of catalystensembles.

An additional important fundamental challenge inhomogeneous catalysis is to gain control over highlyreactive (hypovalent) intermediates such astransition metal carbenoids, nitrenoids,phosphinidenoids, ketene, ketenimine, allene,nitride and oxo-complexes, and their (radical-type)analogues. These intermediates are highly relevantin a variety of C-H activation and C-C, C-O, C-N andC-P bond formation reactions (including formationof ring compounds, new polymers, building blocksfor organic synthesis, etc.). However, they are oftendifficult to control to the desired levels ofselectivity. Avoiding the use of high-energy reagentsto prepare hypovalent intermediates is extremelydesirable from a perspective of sustainability andefficiency. This is (at least in principle) possible bycombining catalysis with electrochemistry (catalytic

electro-synthesis). In this way reactive (hypovalent)intermediates can be directly generated at e.g. theanode of an electrolyzer. This challenging andpromising field of catalytic electro-synthesis ispoorly charted, and clearly deserves more attention.

We will need to focus more on predictive modelingrather than explanatory modeling, translating ouratomic understanding into material or process-design parameters and synthesis strategies. Thiswill allow for atomic-scale resolution in active sitedesign as well as 3D control of meso- andmacroscale structures (e.g. through self-assembly),enabling macroscopic effects like mass transfer.This would include the development of reactionsand processes that do not require functional groupprotection and provide a general strategy towardsfunctional group transformation (important inbiomass conversion).

In theory development, we need to take intoaccount the very different timescales and lengthscales relevant to a proper description of catalysis,e.g. picosecond bond-making and bond-breakingevents at atomic scale up to diffusion and reactionphenomena in meter-sized reactors. Complementaryto theoretical research, investments are also neededin surface science, as the detailed experimentaldescription of the atomic level provided by surfacescience is key to further developments in thecontext of new advanced materials.

Fundamental studies must concentrate both oncatalysts (molecules, materials and preparation)and catalysis (activity, selectivity, stability). Therole of promoters and solvent and support effectsalso needs to be taken into consideration.Developments towards the control of selectivity bygenerating second-sphere effects are particularlyrelevant in the context of homogeneous catalysis,where this area is still fairly unexplored.

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The increasing use of high-throughput methods andtomographic techniques has dramatically increasedthe amount of data that becomes available perexperiment. Handling this data, and understandingcomplexity in catalytic systems, such as thecomplex mixtures in commercial feedstocks(whether from biomass or fossil origin), is a hugechallenge that will require, among other things, thedevelopment of analytical chemistry and data-handling tools beyond the current level

Opportunities for CatalysisAn improved fundamental understanding ofcatalysts and catalytic reactions will unlock manynew opportunities for the application of catalysisand lead to new catalytic routes to new molecules.These advances are key to – and will go hand-in-hand with – the necessary shift towards a moresustainable and economically valuable catalysis,from academic research to industrial applicationlevels.

A prerequisite for tackling the challenges definedabove is the further development of sophisticatedcharacterization tools, capable of mapping activityand chemistry at the surface. This includes theintegration of spatially and temporally resolvedspectroscopy with microscopy methods, as well asreal-time spectroscopy. Time-resolved spectroscopyin particular is key to be able to fully describecatalytic events such as photocatalytic processes. In other cases, completely new tools for probingmolecular catalysts and catalyst surfaces will berequired. Examples of these new tools are free-energy lasers and THz excitation, which can be usedto probe femtosecond dynamics in single bond-breaking events. Synchrotron sources present theopportunity to characterize structural andelectronic changes down to the lifetime of reactiveintermediates in the pico- and nanosecond regime.It is fundamental for the development andimprovement of (homogeneous) catalysis todetermine the reaction mechanisms via reaction

kinetics and diverse spectroscopic studies in orderto identify reaction intermediates.

An important aspect to consider in the context ofthe theory and modeling of realistic catalyticsystems is whether physical insight is possible fromstudying realistic systems or model systems underrealistic conditions. The catalytic truth at atomicscale may be hidden under various “onion rings” of effects that govern the process at larger lengthscales or higher temperatures, like mass transportand diffusion effects. In biocatalysts, small changesremote from the active site can induce significantimprovements. With the newly developed tools,these distant interactions will help to improve alltypes of catalysis. At the same time, experimentalvalidation should be done in realistic systems,bridging the temperature and pressure gaps.

Understanding realistic complex systems willtremendously speed-up progress in all fields ofcatalysis. As an example: recent developments inbioinformatics provide the opportunity to extractand predict the reactivity and structure of complexenzymes, combining data from gene, protein and x-ray databases. Translation of concepts like theseto homogeneous and heterogeneous catalysis willunlock completely new possibilities.

In order to develop catalysts based on abundantfirst-row metals, we need to understand thereactivity of these catalyst complexes in detail,including their radical-type behavior. After all,these complexes can be based on non-innocent andinnocent ligands, resulting in complementaryreactivity. These ligands have more of a generalapplicability and can thus minimize the metal coststhrough lower catalyst loadings. We should find away to reduce the time for ligand development viamodular approach and in particular usingcomputation, which should become the main toolfor ligand design instead of the present broadscreening approach. In addition, the development

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of metal-free catalysts should be further exploredby developing new catalyst systems and concepts.In these particular systems, traditionalspectroscopic techniques (IR, NMR) are lessconclusive, and require less established and oftenmore difficult to interpret characterization tools,such as EPR and Mössbauer spectroscopy, as wellas X-ray absorption and emission techniques as acomplement to the development of new syntheticprocedures.

The increased understanding we gain fromcharacterization and theory should give us anopportunity to combine our insights and to gainimproved control over the synthesis of newcatalysts, both heterogeneous and homogeneousand their design from the atomic scale upward. Forheterogeneous catalysts, atomic-scale precisionshould be combined with the 3D meso- andmacroscale location of components to createrealistic, strong and stable new catalysts. Thecapacity to build well-defined systems viananomanipulation and the possibility of performingcatalysis on a single nanoparticle are identified aslong-term development opportunities. Thecontrolled synthesis of hybrid materials, which

combine homogeneous building blocks withheterogeneous surfaces, will give a powerfulimpulse especially to the fields of cascade reactionsand solar fuels.

Finally, chemoselectivity needs more attention.Now that we are contemplating complex feedstocks,reaction cascades, one pot syntheses, CO2-activation and systems catalysis, the rational designof targeted catalytic functionalities that do notinterfere with other functionalities will beimportant. Catalysts would be desirable that canselectively convert a single functionality in complex,multifunctionalized molecules.

Dutch Strengths inFundamentals andMethodologyA fundamental understanding catalysis at all scalesis one of the true strengths of Dutch catalysisresearch. In heterogeneous catalysis, control overthe size and morphology of nanometer-scale activeclusters had been proven for various systems, yet

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Gang Yang, Evgeny Pidko and Emiel Hensenstudied the siting of heteroatoms in zeolite BEAand the resulting Lewis acidity with periodicdensity functional theory (DFT) calculations.They found that the Lewis acidity of substitutedzeolites strongly depends on the crystallographiclocation of the heteroatoms. The presence ofpaired lattice sites in Sn–BEA zeolitesubstantially enhances Lewis acidity, whichclearly distinguishes Sn–BEA from its Ti- and Zr-substituted analogues (J. Phys. Chem. C,2013, 117 (8), pp 3976–3986).

Modeling Lewis acidity in Beta-zeolites

the (self-)assembly of these clusters intomacroscopic systems remains an interestingchallenge. In homogeneous catalysis, concepts fromnature’s catalysts, such as the capacity of methanemonooxygenases to convert methane to methanol,have been a proven source of inspiration and at thesame time a challenge to aim for.

Dutch research on theory and modeling hastraditionally been strong but now risks losing itsplace at the forefront. Strong fundamental tooldevelopment is still available in Amsterdam (theADF package of the Amsterdam Centre forMultiscale Modelling), and efforts to strengthen themodeling expertise are in progress at otheruniversities. These efforts should be stimulated andfurther expanded.

The development of homogeneous catalysts for thebulk and fine chemical industries, including the

application of such systems, is represented at a highlevel in the Netherlands.

Atomic-resolution spectroscopy under industrialoperating conditions has undergone considerabledevelopment in the past decade. Many of the newtools were developed and first applied in theNetherlands. Various light and X-ray tomographytools have been developed here to study catalyticprocesses in operando. Further improvements inspatial and temporal resolution, labelingtechniques, and chemical imaging are required toimprove our fundamental understanding of real-lifecatalytic systems. Large research infrastructuralfacilities are either present in the Netherlands(NMR, HFML, TEM) or scientists have good accessto international facilities that are not availablenationally (synchrotron and neutron sources,FELs). Research in general would benefit fromsetting up a national platform for (the integration

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Compared to traditional, so-calleddistributive catalysis in which substrateand catalyst only meet once, processivecatalysis is more efficient because thereactants associate and remain connected,faciliating multiple round of reactionsbefore they separate. Stijn van Dongen,working with professors Roeland Nolteand Alan Rowan, developed a C-shapedbiohybrid catalyst that operates in thisfashion (Van Dongen et al., NatureChemistry, 5, 945-951 2013). It binds to a DNA plasmid and while moving along itcleaves the chain at specific locations(AAA sites) in a processive manner. Whenthe loading of the catalyst to the DNAchain is prevented by a peptide themechanism changes from processive todistributive because the cleavage reactioncan only occur randomly.

A biohybrid protein clamp (blue) provided with 3 manganese porphyrin catalysts(green) glides along a double stranded DNA chain, while cutting it at AAA sites(picture ICMS Animation Studio, TUe)

Processive catalysis

of) experimental techniques. Catalysis research as afield where many of these experimental techniquescome together can play a pioneering role here.

Finally, the Dutch school of catalysis is known forits holistic approach to catalysis, which combinesthe aspects stressed above: theoreticalunderstanding, spatially and temporally resolvedspectroscopy at high resolution, and 3D atomicdesign and synthesis. The strong cooperation andclose relationship between industrial and academicresearch in the Netherlands provides the idealframework for the transition from understandingsmall-scale model systems to understanding large-scale real-life systems.


Areas of ResearchIn the context of this Roadmap for Catalysis, it isclearly the intention that developments mentionedhere in “Fundamentals and Methodology” willbenefit all other topics that have been identified aspriorities in the preceding chapters. Addressing the previously indicated challenges will requireconcerted and multidisciplinary actions that willtake advantage of the existing strengths in theNetherlands and strengthen those areas that areless explored, as in the case of Theory andModeling. A set of key research focus areas isdiscussed below:

Optimal control over chemical systems andreactions A detailed understanding of chemical kinetics andreactivity, focused particularly on structure- activityrelationships, will be the basis for the rationalizationof reaction mechanisms, leading to an improveddesign of catalysts and catalytic processes: higherefficiency, stability and selectivity. Simultaneously,

the ability to design, prepare and characterize newmaterials with 3D control at atomic or molecularresolution and at various length scales must bedeveloped. New concepts in ligand design must beexplored to allow for catalysis with more abundant,first-row transition metals. The molecular chemistryof these catalysts and metal complexes needs furtherdevelopment. The availability of characterizationtools for a diamagnetic system like Pd has led to a good understanding of this system, but theorganometallic chemistry of for instance Fe is hardlyexplored. Apart from activity, stability of this type ofcatalyst needs to be examined. The development offundamentally new homogeneous catalysts needsattention, e.g. in the field of organocatalysis, but alsophoto-redox catalysts, and molecular redox catalysts.The latter may find more use when electrical energywould be more abundant through solar conversionroutes.

In order to improve the catalytic transformations inparticular in homogeneous catalysis novel syntheticmethods for ligand preparation as well as predictivemodeling for achieving sophistication in ligandengineering in order to develop ligands with desiredchemo-, stereo- and regioselectivity and high valuesof TOF and TON are required. Another importantaspect would be a development of heterobimetaliccatalysis in order to provide cooperative catalysiscoming from two different metals. Only a fewexamples are known, mainly due to the lack ofcorresponding ligands to bind to different (soft andhard) metals.

Predictive modelingTheory, multiscale modeling, and computationalchemistry together form one of the pillars of thestrategy proposed in this Roadmap for Catalysis.The development of descriptive and predictivemethodologies based on input from newspectroscopic tools will provide a much moredetailed insight into the parameters that play a rolein catalysis. Research in this area will benefit from

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development in the adjacent fields of complexityand big data research. Rather than simplyunderstanding such parameters, the focus will nowbe on predicting which set of conditions will bemost suitable for a given catalytic process.

Understanding complex and real systemsEnhanced spectroscopy and microscopy on realistic systems, incorporating 3D atomic-resolution characterization techniques, in situ and ex situ methodologies, broad time resolution,and data processing and analysis tools (e.g.dephasing, multivariate procedures) will allow theidentification of the key descriptors that can serveas the basis for design rules for new catalysts andmolecules. This field is strong for heterogeneouscatalysis, but needs development for homogeneoussystems, especially with respect to homogeneouscatalysis with first-row transition metals.

In this perspective, the use of computational toolsto better understand spectroscopic measurementswhich are otherwise difficult to interpret (e.g. EPR,Mössbauer, XAS/XES spectroscopy) in catalysisresearch is also important. This should again beconcerted with the development of theoreticalmethods that incorporate more realistic, morecomplex systems, moving away from smallmolecular models, model surfaces, clusters andsingle molecules.


• Computational methods that account for thecomplexity of chemical/catalytic processes onvarious timescales and length scales;

• A transient view of catalysis that accounts for out-of-equilibrium processes, instead of the currentsteady-state view;

• Precise control of morphology, composition anddefect structure, leading to influence optical,

electronic and catalytic properties on multiplescales;

• A toolbox to translate chemical descriptors ofcatalysis and catalysts into predictors and designrules for new molecules and synthetic methods;

• The science-based development of highly stablecatalytic molecules and materials with self-repairand self-assembling properties;

• Mechanistic insight by combining spectroscopywith computational spectroscopy;

• Control and efficient generation of highly reactive(hypovalent) catalytic intermediates;

• The precise control of selectivity in synthesis andcatalysis, including regulation mechanisms toaccommodate changes in reaction conditions (e.g.as observed in natural photosynthesis);

• The targeted activation of specific catalytic sitesand the control of reaction speeds andmechanisms, allowing for a cost-effectiveutilization of catalyst materials and an efficientreplacement of noble metals by cheaper and moreabundant materials;

• Novel synthetic methods for ligand preparation aswell as predictive modelling for achievingsophistication in ligand engineering in order todevelop ligands with desired chemo-, stereo- andregioselectivity and high values of TOF and TON;

• New homogenous (organo)catalysts for photo-redox catalysis, molecular redox catalysis andchallenging group-transfer reactions;

• Chemoselective catalysts that can selectivelyconvert a single functionality in complex,multifunctionalized molecules.

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Annexes 69

Catalysis – Key to a Sustainable Future | Annexes

Core and supporting team

Core team

Dr. M. Barroso (Utrecht University)

Prof. J.H. Bitter (Wageningen University)

Dr. Q.B. Broxterman (DSM ChemicalTechnology R&D B.V.)

Prof. B. de Bruin (University of Amsterdam)

Dr. F.R. van Buren (retired from Dow)

Prof. U. Hanefeld (Delft University ofTechnology)

Prof. E.J.M. Hensen (Eindhoven Universityof Technology)

Prof. S. Otto (University of Groningen)

Prof. E.T.C. Vogt (Albemarle Catalysts B.V.,Utrecht University)

Prof. B.M. Weckhuysen (Utrecht University)

Project manager

Dr. W. Hesselink (retired from Shell)

Process manager

Dr. B. de Klerk

Support office

Dr. I.H.L. Hamelers (NWO)

Dr. I.S. Ridder (NWO)

Peer reviewers

Dr. C. Alma (VNCI)

Dr. K. van der Wiele (retired fromAlbemarle Catalysts BV)

People present at workshop in Jan. 2014

Dr. P.L. Alsters (DSM Chemical TechnologyR&D B.V.)

Dr. S. van Bavel (Shell)

Dr. A.E.W. Beers (Cabot Corporation)

Dr. P.H. Berben (BASF)

Prof. E. Bouwman (Leiden University)

Dr. P.C.A. Bruijnincx (Utrecht University)

Dr. R. Bulo (Utrecht University)

Dr. I. Daems (ExxonMobil)

Prof. B.-J. Deelman (Arkema / UtrechtUniversity)

Dr. M.C. Feiters (Radboud UniversityNijmegen)

Prof. B.L. Feringa (University of Groningen)

Dr. J. Gascon (Delft University ofTechnology)

S. Goeree (NWO)

Dr. S. Grecea (University of Amsterdam)

Dr. K. Gurram (Sabic)

Prof. H. Hiemstra (University ofAmsterdam)

Dr. M. Hollestelle (NWO)

Dr. M.J.G. Janssen (ExxonMobil)

Dr. P.E. de Jongh (Utrecht University)

Dr. L.B.F. Juurlink (Leiden University)

Prof. F. Kapteijn (Delft University ofTechnology)

Prof. S.R.A. Kersten (University of Twente)

Dr. G. van Klink (Avantium)

Dr. E.G.M. Kuijpers (BASF)

Dr. H.P.C.E. Kuipers (Shell)

Dr. N. van der Puil (Avantium)

Prof. R.J.M. Klein Gebbink (UtrechtUniversity)

Prof. M.T.M. Koper (Leiden University)

Prof. J.P. Lange (Shell/University of Twente)

Prof. L. Lefferts (University of Twente)

Prof. G. Mul (University of Twente)

Dr. T.A. Nijhuis (Eindhoven University ofTechnology)

Dr. T. Noël (Eindhoven University ofTechnology)

Dr. E. Otten (University of Groningen)

Dr. R. Parton (DSM Chemical TechnologyR&D B.V.)

Dr. E.A Pidko (Eindhoven University ofTechnology)

Prof. J.N.H. Reek (University of Amsterdam)

Prof. G. Rothenberg (University ofAmsterdam)

Dr. M. Ruitenbeek (Dow)

Prof. A. Schallmey (University ofAmsterdam)

Dr. E. Scott (Wageningen University)

Prof. K. Seshan (University of Twente)

Dr. N.R. Shiju (University of Amsterdam)

Dr. J.C. Slootweg (VU UniversityAmsterdam)

Dr. J.T.C.M. Sprangers (Ministry ofEconomic Affairs)

Dr. R. van Summeren (DSM ChemicalTechnology R&D B.V.)

Dr. R.J.A.M. Terörde (BASF)

Dr. J.I. van der Vlugt (University ofAmsterdam)

Dr. A.M. Ward (Sabic)

Prof. T. Weber (Shell/Eindhoven Universityof Technology)

Dr. S.M.A. de Wildeman (AMIBM)

Input for the themes

Dr. P.L. Alsters (DSM Chemical TechnologyR&D B.V.)

Prof. R.A.T.M. van Benthem(DSM/Eindhoven University of Technology)

Dr. P.H. Berben (BASF)

Dr. W.R. Browne (University of Groningen)

Dr. P.C.A. Bruijnincx (Utrecht University)

Dr. R. Bulo (Utrecht University)

Dr. P.L. Buwalda (Avebe)

Prof. G. Centi (University Messina, Italy)

Prof. B. Dam (Delft University ofTechnology)

Prof. B.-J. Deelman (Arkema/UtrechtUniversity)

Dr. G. van Doremaele (Lanxess)

Dr. R. Duchateau (Sabic)

Prof. G. Eggink (Wageningen University)

Dr. J. Flapper (Akzo Nobel)

P. Flippo (Arizona chemical)

Prof. M.W. Fraaije (University ofGroningen)

Dr. M.C.R. Franssen (WageningenUniversity)

Prof. J. Gascon (Delft University ofTechnology)

Prof. J.J.C. Geerlings (Shell/Delft Universityof Technology)

Dr. P.J.A. Geurink (Akzo Nobel)

J. Groen MBA (Biorizon)

Prof. F.M.F. de Groot (Utrecht University)

Dr. R. Hage (Catexel)

Dr. W.G. Haije (ECN)

Dr. S.R. Harutyunyan (University ofGroningen)

Dr. J. van Haveren (Wageningen ResearchCenter)

Prof. H.J. Heeres (University of Groningen)

Prof. V. Hessel (Eindhoven University ofTechnology)

Dr. J.P. Hofmann (Eindhoven University ofTechnology)

Prof. W.T.S. Huck (Radboud UniversityNijmegen)

Dr. M.J.G. Janssen (ExxonMobil)

70 List of contributors

Prof. K.P. de Jong (Utrecht University)

Prof. P.E. de Jongh (Utrecht University)

Prof. F. Kapteijn (Delft University ofTechnology)

Prof. R.M. Kellogg (Syncom)

Prof. R.J.M. Klein Gebbink (UtrechtUniversity)

Dr. J.H. Koek (Unilever)

Prof. M.T.M. Koper (Leiden University)

Prof. G.-J. Kramer (Shell/Leiden University)

Dr. J. Lang (Evonik, Germany)

Prof. J.-P. Lange (Shell/University ofTwente)

Prof. K.U. Loos (University of Groningen)

Prof. G. Mul (University of Twente)

Dr. G.R. Meima (Dow)

Dr. T.A. Nijhuis (Eindhoven University ofTechnology)

Prof. R.V.A. Orru (VU UniversityAmsterdam)

Dr. R. Parton (DSM Chemical TechnologyR&D B.V.)

Dr. E.A. Pidko (Eindhoven University ofTechnology)

Dr. P. Poechlauer (DSM ChemicalTechnology R&D B.V.)

Dr. V. Quiroga (Lanxess)

Prof. J.N.H. Reek (University of Amsterdam)

Prof. G. Rothenberg (University ofAmsterdam)

Prof. F.P.J.T. Rutjes (Radboud UniversityNijmegen)

Prof. J.P.M. Sanders (WageningenUniversity)

Prof. R.A. van Santen (EindhovenUniversity of Technology)

Dr. W.R.K. Schoevaart (Chiralvision)

Dr. E. Scott (Wageningen University)

Dr. W. Sederel (Biobased Delta)

Dr. J. Severn (DSM Chemical TechnologyR&D B.V.)

Prof. R.P. Sijbesma (Eindhoven University ofTechnology)

Dr. J.C. Slootweg (VU UniversityAmsterdam)

Dr. R. van Summeren (DSM ChemicalTechnology R&D B.V.)

Dr. G. Verspui (Mercachem)

Dr. J.C. van der Waal (Avantium)

Prof. T.T. Weber (Shell)

Dr. M. Zuideveld (Sabic)

71

Catalysis – Key to a Sustainable Future | Annexes

Background documentsTechnology Roadmap Catalysis – Catalysis, Key to sustainability, 2001

Chemical Sciences and Engineering Grand Challenges, EPSRC, IChemE, RSC, 2009

Technology development for the production of biobased productsfrom biorefinery carbohydrates—the US Department of Energy’s“Top 10” revisited, Joseph J. Bozell, and Gene R. Petersen, GreenChem., 2010, 12, 539–554

Catalysis. A key technology for sustainable economic growth,GECATS, 2010

International Assessment of Research and Development in Catalysisby Nanostructured Materials, Robert Davis (ed.), London, 2011

The Dutch Research Agenda, Royal Netherlands Academy of Artsand Sciences, 2011

New Earth, New Chemistry, Actieagenda Topsector Chemie, 2011

De sleutelrol waarmaken. Routekaart Chemie 2012-2030, VNCI, 2012

Solar Fuels and Artificial Photosynthesis - Science and innovation tochange our future energy options, Royal Society of Chemistry, 2012

Energieakkoord voor Duurzame Groei, Den Haag, 2013

Technology Roadmap Energy and GHG Reductions in the ChemicalIndustry via Catalytic Processes, IEA, DECHEMA, ICCA, 2013

Chemistry & Physics: Fundamental for our Future, Vision paper 2025, Commissie-Dijkgraaf, 2013

ACTS Advanced Chemical Technologies forSustainability

ADF Amsterdam Density Functional package

ASPECT Advanced Sustainable Processes by EngagingCatalytic Technologies

BBE BioBased Economy

BE-Basic Biotechnology based Ecologically BalancedSustainable Industrial Consortium

CatchBio Catalysis for Sustainable Chemicals fromBiomass

CCS Carbon Capture and Sequestration

COST European Cooperation in Science andTechnology

DECHEMA DECHEMA Society for Chemical Engineeringand Biotechnology

DFT Density Functional Theory

DNA Deoxyribonucleic acid

DPI Dutch Polymer Institute

ECN Energy Research Centre of the Netherlands

EPR Electronic Paramagnetic Resonance

EPSRC The Engineering and Physical Sciences ResearchCouncil, UK

EST Eni Slurry Technology

EU European Union

FCC Fluid Catalytic Cracking

FDCA 2,5-FuranDiCarboxylic Acid

FEL Free-Electron Laser

FTO Fischer–Tropsch-to-Olefins

GDP Gross Domestic Product

GECATS GErman CATalysis Society

GHG GreenHouse Gas

HFML High Field Magnet Lab

HSE Health, Safety, Environment

IBOS Integration of Biosynthesis and OrganicSynthesis

ICCA International Council of Chemical Associations

IChemE Institution of Chemical Engineers

IEA International Energy Agency

InSciTe Institute for Science & Technology

IOP Catalysis Innovation-oriented Research Program Catalysis

IR Infra-Red

LCA Life-Cycle-Assessment

MOF Metal-Organic Framework

MTO Methanol To Olefins

NCCC The Netherlands’ Catalysis and ChemistryConference

NGO Non-Governamental Organization

NIMIC Nano-IMaging under Industrial Conditions

NIOK Netherlands Institute for Catalysis Research

NMR Nuclear Magnetic Resonance

NRSCC Netherlands Research School CombinationCatalysis

NWO The Netherlands Organisation for ScientificResearch

OCM Oxidative Coupling of Methane

PHAs Polyhydroxyalkanoates

PO PolyOlefin

PPP Public-Private Partnership

PV PhotoVoltaic

RAFT Reversible Addition-Fragmentation chainTransfer

RSC Royal Society of Chemistry

SET-LRP Single-electron transfer living radicalpolymerization

SMEs Small and medium-sized enterprises

TASC Technology Areas for Sustainable Chemistry

TEM Transmission Electron Microscopy

THz TeraHertz

TOF TurnOver Frequencies

TON TurnOver Numbers

VFA Volatile Fatty Acids

VIRAN Industrial Advisory Board of NIOK

VNCI Association of the Dutch Chemical Industry(Vereniging van de Nederlandse ChemischeIndustrie)

XAS X-ray Absorption Spectroscopy

XES X-ray Emission Spectroscopy

72 Abbreviations

catalysis – key to a sustainable future · cleaner, more efficient, and economically viable...

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