cost action fp1306 - photo-catalysis · fp1306 cost action joint wg1 & wg3 meeting lisbon,...

FP1306 COST Action

Joint WG1 & WG3 Meeting

Lisbon, 26-27 September 2016

1

COST is supported by the EU Framework ProgrammeHorizon 2020

COST Action FP1306

“Valorisation of lignocellulosic biomass side streams for sustainable

production of chemicals, materials & fuels using low environmental

impact technologies” (LIGNOVAL)


SANA Malhoa, Lisbon, Portugal

September 26-27, 2016

FP1306 COST Action



2


FP1306 COST Action (LIGNOVAL):

Working Group 1 + Working Group 3 Meeting, Lisbon 2016

Organized by: Lígia O. Martins, ITQB-NOVA, Portugal

Tarja Tamminen, VTT, Finland Ulrika Rova, Luleå Univ, Sweden

& Prof. Rafael Luque, University of Cordoba, Spain, Action Chair

Prof. Kostas Triantafyllidis, Aristotle University of Thessaloniki, Greece, Action Vice-Chair

COST (European Cooperation in Science and Technology) is a pan-European intergovernmental framework. Its mission is to enable break-through scientific and technological developments leading to new concepts and products and thereby contribute to strengthening Europe’s research and innovation capacities. www.cost.eu This brochure was produced with the support of COST Association.

FP1306 COST Action



3


MONDAY, 26 September 2016

9:00 Registration 9:25

Opening Welcome

Chair: Kostas Triantafyllidis

09:30 “From structural understanding to valorization: the structure of technical lignins from

different fractionation processes”

Claudia Crestini

10:05 “High-resolution mass spectrometry for characterization of biomass products”

Ondřej Mašek, Michele Ghidotti, Logan Mackay, Javier Fermoso, Julian Pietrzyk, and Daniele

Fabbri

10:25 “Theoretical study of lignin β-O-4 linkages – Conformational preferences and coupling to

molecular vibrations and FTIR spectra”

Søren Barsberg and Janka Dibdiakova

10:45 Coffee Break

11:00 “Toward Carbon Fibers from Single Component Kraft Lignin Systems; optimization of Chain

Extension Chemistry”

Dimitris S. Argyropoulos, Hasan Sadeghifar, S. Sen and Shradha

11:25 “Vanadium catalyzed aerobic oxidative processes for lignin degradation”

E. Amadio, C. Zonta and G. Licini

11:45 “Electrochemical conversion of lignin – a promising approach to obtain added value

products”

T. Höfler, P. Neu, M. Mittelbach, S. Schober

12:00 Lunch and Networking

Chair: Dimitris Argyropoulos

14:00 “Catalytic fast pyrolysis of various types of lignin: effect of isolation method, biomass source

and biomass pretreatment”

P. Lazaridis, C. Nitsos, L. Matsakas, U. Rova, P. Christakopoulos and K. Triantafyllidis

14:20 “Study of the influence of zeolite and lignin type on the lignin pyrolysis products”

Jelena Milovanović, Rafael Luque, Roman Tschentscher, Antonio A. Romero, Hangkong Li and

Kaimin Shih

14:40 “High throughput single stage continuous hydrodeoxygenation of liquid phase pyrolysis oil”

Nikolaus Schwaiger, Roland Nagl, Klaus Schlackl, Klara Treusch, Thomas Pichler, Manuel

Menapace, Dominik Heinrich, Manuel Tandl, Anna Mauerhofer, Peter Pucher and Matthäus

Siebenhofer

15:00 “Lignin breaking down: Comparison between solid lignin and black liquor base catalyzed

depolymerization in order to produce phenolic compounds”

Xabier Erdocia, Javier Fernández-Rodríguez, María González Alriols and Jalel Labidi

15:15 Coffee Break

15:30 “Willow lignin oxidation and depolymerisation under low cost ionic liquid”

Raquel Prado, X. Erdocia, G. F. De Gregorio, J. Labidi and T. Welton

FP1306 COST Action



4


15:50 “Valorization of an invasive wood species by lignin extraction with low environmental impact

solvents”

M. Graça V. S. Carvalho, Ana R. Fernandes, Jorge M.S. Rocha and Abel G. Ferreira

16:05 “Selective transformations of biomass-derived organic compounds using heterogeneous

photocatalysis”

Agnieszka Magdziarz and Juan C. Colmenares

16:20 WG1 + WG2 Discussion

19:30 Dinner

TUESDAY, 27 September 2016

Chair: Ulrika Rova

09:00 “Impact of lignin properties on maximum achievable monomer yields for C-O cleaving lignin

depolymerization approaches”

Thanaphong Phongpreecha, Nicholas Hool, Kendall Christy and David Hodge

9:35 “Chemoenzymatic fractionation and characterization of pretreated birch outer bark”

Anthi Karnaouri, Heiko Lange, Claudia Crestini, Ulrika Rova and Paul Christakopoulos

9:55 “Applications of laccase treatments to modify lignin properties

Anna Kalliola, Martta Asikainen, Taina Ohra-aho and Tarja Tamminen

10:15 “Directed evolution of bacterial lignolytic enzymes”

Vânia Brissos, Mara Marques, Diogo Tavares, Sónia Mendes and Lígia O. Martins

10:35 Coffee Break

Chair: Tarja Tamminen

11:00 “New added-value chemicals, polymers and materials from renewable resources; a few

examples @CICECO”

Armando J. D. Silvestre

11:25 “Energy production through syngas from ligno-cellulosic waste”

Simona S. Merola, Adrian Irimescu, Fernando Colmenares and Janka Dibdiakova

11:45 “Lignin vinyl esters and their co-polymers with styrene, divinylbenzene and

triethoxyvinylsilane”

Beata Podkościelna, Oihana Gordobil, Anastasia V. Riazanova, Jalel Labidi, Olena Sevastyanova

12:15 Concluding Remarks

12:30 Lunch

POSTER

“Grafting of wheat straw fibers with PCL via ring-opening polymerization for PLA reinforcement”

I.Kellersztein and A. Dotan

FP1306 COST Action



5


From structural understanding to valorization: the structure of technical lignins from

different fractionation processes

Claudia Crestini Dipartimento di Scienze e Tecnologie Chimiche. Tor Vergata University, Via della Ricarca Scientifica, 00133, Roma, Italy

[email protected]

Introduction

Is it possible to increase the sustainability of industrial processes while maintaining or increasing the

competitiveness of enterprises? Can lignin be used as as a strategic renewable resource alternative to fossil fuels?

Although fundamental research has historically focused on converting lignin to chemicals, materials, and fuels,

very little of this effort has been translated into commercial practice. This is mainly due to the wide lignin

heterogeneity and diversity that imply difficulties in: understanding the molecular structure, getting

homogeneous and constant batches, understanding its fundamental chemistry and controlling multifunctionality

and associative interactions.

The strategy to overcome such barriers lies in accomplishing careful structural evaluation of the specific lignin

sources through the development of specific analytical protocols.

In fact, as a multifunctional polymer displaying many aliphatic and phenolic OH groups, lignin offers plenty of

opportunities for functionalization. Over the past two decades, advances in analytical and spectroscopic

techniques have dramatically refined our understanding of lignin structure. Kraft lignin is generally accepted to

be of a highly condensed nature with the occurrence of significant amounts of biphenyl and diphenylmethane

units.

Recent work in our laboratory, has been focused at re-examining the structure of various lignins using

quantitative 2D-NMR pulse sequences.

This effort offered a novel, accurate picture of MWL, different kraft and organosolv lignins.

The accumulated knowledge, has as such refined our view of the structure of kraft and organosolv lignin as

being dramatically different polymers from what was originally accepted.

Experimental

HSQC and QQ-HSQC NMR spectra were carried as previously reported.1,3

31P-NMR and GPC analysis were performed as previously reported.1,3

Results and Discussion

The lignin spectra of different kraft lignins show that the major native structures of native lignin, such as aryl

glycerol--aryl ethers (-O-4) phenyl coumaran (-5) and pinoresinol (-) are present in lignin after pulping.

Their intensities varies depending on the degree of pulping. The amounts of -O-4 and -5 decrease significantly

upon pulping and do not constitute any longer the main linking pattern. The - subunits are not reactive under

kraft pulping conditions and appear to accumulate in the kraft lignin. -1 and dibenzodioxocin lignin subunits

were not detected in the kraft lignin samples.

The oxygenated aliphatics area shows correlation peaks that correspond to and hydroxyacids or various

homologues. Arylglycerol and cinnamyl alcohol terminal units were also seen to be present in significant

amounts.

Lignin carbohydrate complexes signals relative to -O-alkyl/-O-4 units are present in all the samples. These

signals were previously assigned as the linkage of the - position of lignin with primary hydroxyls in

carbohydrates. Lignin carbohydrate complexes, of the phenyl- glycoside type, are seen to be present in much

lover amounts.

Aryl enol ether and stilbene moieties were found to be present in significant amounts.

While stilbene are stable to bleaching processes, the aryl enol ethers can be easily degraded upon oxygen

delignification. Partially bleached lignins show a decreased amount of such units.

For a long time, our understanding of kraft lignin structure was based on model compound experiments and on

structural analyses efforts of residual lignin. As such it was concluded that extensive condensation of lignin

occurs during kraft pulping. However other studies cast doubt about the occurrence of significant condensation

chemistries occuring during kraft pulping. Diarylmethane substructures have been considered among the main

condensed moieties formedd upon kraft pulping. They are produced from formaldehyde, generated by the

formation of stilbenes from phenyl coumaran units, reacting at the 5 position of the aromatic ring in phenolic

FP1306 COST Action



6


units, or by condensation of quinone methides intermediates with other phenolics. The samples examined during

our work did not show such structures, casting doubt for the occurence of this reaction to any significant extent.

4-O-5 lignin subunits are easily detectable in softwood lignins by the C upfield shift from 110-112 to <110

ppm. Only low amounts of such condensed units could be found in some of the samples.

The diphenyl lignin subunits display a correlation signal at C120-122. Such signals are partially overlapped

with the CH-6 guaiacyl signals. Thus it is not possible to have a quantitative evealuation of their abundance.

They are thought to accumulate upon pulping. However recent results on MWL structural elucidation show that

such units are present only as terminal phenolics.

HSQC spectra of kraft lignin show intense aliphatic signals. They correspond to aliphatic chains and partially

oxidized aliphatic chains. However, they do not match with the main extractives signals. These signals appear to

be accumulated upon pulping and are generated by extensive side-chain reduction processes.

Finally, the accurate analysis of the aromatic correlation signals show the presence of a wide viariety of alpha-

oxidized aromatic rings.

Conclusions

Over the past two decades, advances in analytical and spectroscopic techniques have dramatically refined our

understanding of lignin structure. The accumulated knowledge, has as such refined our view of the structure of

kraft lignin as being a dramatically different polymer from what was originally accepted .

These features now reveal characteristics for kraft lignin that may pave the way to addressing key limitations and

present our industry with possibilities for new applications.

References

1. Sette, M., Wechselberger, R., Crestini, C. Elucidation of lignin structure by quantitative 2D NMR (2011) Chemistry - A

European Journal, 17 (34), pp. 9529-9535.

2. Marco Sette, Heiko Lange, Claudia Crestini. Quantitative HSQC Analyses of Lignin: A Practical Comparison

Computational and Structural Biotechnology Journal 6 (7), 2013, e201303016

3. Crestini, C., Melone, F., Sette, M., Saladino, R. Milled wood lignin: A linear oligomer (2011) Biomacromolecules, 12

(11) 3928-3935

FP1306 COST Action



7


High-resolution mass spectrometry for characterization of biomass products

Ondřej Mašek1*, Michele Ghidotti

2, Logan Mackay

3, Javier Fermoso

4, Julian Pietrzyk

1, and Daniele Fabbri

2

1UK Biochar Research Centre, University of Edinburgh, King’s Buildings, Edinburgh, EH9 3FF, UK 2 Interdepart. Centre for Ind. Research “Energy and Env.”, Univ. of Bologna, via S. Alberto 163, I-48123 Ravenna (Italy)

3School of Chemistry, University of Edinburgh, King’s Buildings, Edinburgh, EH9 3FJ, UK 4IMDEA Energy Institute, Thermochemical Processes Unit, 28935 Móstoles, Spain.

*[email protected]

Introduction

Biomass and biomass-derived products are often complex and present numerous challenges in analysis and

characterization. Well established methods such as GC-MS have proved to be very useful in providing insights

into composition of various biomass-derived products, such as fuels and chemicals; however, their capabilities

are limited and often only a small fraction (<300Da) of compounds present in complex mixtures can be

identified. In this presentation we will show results obtained by characterization of different lignins and

pyrolysis oils by high-resolution mass spectrometry, using ESI-FT-ICR-MS instrument.

Experimental

Corn stalk pyrolysis bio-oils produced at temperatures 350-650°C were diluted 1:10 in deionized water and

centrifuged to precipitate the tar fraction. The aqueous fraction was then diluted 1:100 in methanol and analysed

with FT-ICR-MS. A total of 500 scans were acquired for each spectrum (syringe infusion) using a 8 MW

acquisition size (broadband) by negative mode electrospray ionization (capillary voltage 4kV) on a Bruker

SolariX 12T FT-ICR-MS. Solutions were analysed also with an Agilent 7820/5977 GC-MS.


Due to the high resolution of the FT-ICR-MS, it was possible to detect a much larger number of compounds and

in a wider range of molecular weights than what is possible using GC-MS. This allowed study of differences in

composition of lignins

and pyrolysis oils

derived from different

processes and

processing conditions,

as shown in Fig. 1 and

Fig. 2.

Figure 1. Van Krevelen diagrams based on FT-ICR-MS analysis of three lignin samples extracted from pyrolysis liquids

produced by three different pyrolysis units from identical wood feedstock. The color indicates relative abundance of

individual compounds.

Figure 2. a) Distribution of oxygenated species in corn stalk bio-oil with negative ESI-FT-ICR-MS, b) Chromatograms of

corn stalk bio-oils produced at 350°C (CSO350) and 650°C (CSO650) determined by GC-MS

Conclusions

This work showed a great potential of using high-resolution mass spectrometry for investigation of complex

biomass-derived mixtures, such as pyrolysis oils, and materials, such as lignins derived by different processes,

opening new areas of research and applications. Combination of GC-MS and FT-ICR-MS techniques allows

description of composition of complex mixtures from volatile (monomeric) to non-volatile (oligomeric)

compounds, and in-depth investigation of effects of process conditions and catalysts.

FP1306 COST Action



8


Theoretical study of lignin β-O-4 linkages – Conformational preferences and coupling to

molecular vibrations and FTIR spectra

Søren Barsberg1* and Janka Dibdiakova

2

1Uni. of Copenhagen,Rolighedsvej 23, DK-1958 Frederiksberg, Denmark, 2NIBIO, Høgskoleveien 8, NO-1430 Ås, Norway

*[email protected]

Introduction

The conformational preferences of β-O-4 linkages are of basic importance for lignin reactivity and vibrational

properties. Information from methods such as Raman and FTIR spectroscopy depends non-trivially on such

preferences. Experimental studies can provide information on lignin structure, but theoretical methods can give

additional unique information essential for interpreting experimental studies [1-3]. We provide here a Density

Functional Theory (DFT) based case study of a syringyl β-O-4 model dimer.

Experimental

The software package Gaussian 09 was used for all calculations. The B97-1 functional was used to optimize

structures and obtain vibrational frequencies and IR intensities. All-positive frequencies ensured a genuine

minimum energy structure. The polarization consistent basis sets pc-1 and pc-2 (or reduced versions) were

applied. Single point energies ESCF were obtained by the M06-2X functional and 6-31+G(d,p) basis set. The

enthalpy of each structure was calculated as H = ESCF + ΔHcorr, where ΔHcorr is vibrational enthalpy correction.


The lowest enthalpy structures of both the threo (see fig. 1) and erythro dimer form a double eight-membered H-

bonded ring with in total 13 atoms (three shared atoms). The Cα and Cγ hydroxyls are H-bond donating to the

two methoxy oxygens of the non-phenolic ring. The impact of the specific H-bonding state of these hydroxyl

donors on dimer vibrations and FTIR spectrum is profound, where especially hydroxyl vibrational modes couple

strongly to dimer conformational state. Thus H-bonding can result in significant positional shifts and intensity

enhancement of such modes, as comparison of the fig. 1 two top spectra clearly shows.

Figure 1. (Right) Model structures: fully H-bonded, non-H-bonded threo dimer, non-phenolic model, phenolic model. (Left)

B97-1/pc-1 predicted harmonic frequency FTIR spectra of model structures (same order from the top down).

For G and especially S–type lignin the conformational freedom of β-O-4 linkages is restrained by H-bonding that

forms semi-rigid ring structures. This reduces reactivity and has significant impact on FTIR spectra.

References

1. S. Barsberg, Theo. Chem. Acc., 134 33 (2015).

2. S. Besombes, D. Robert, J.-P. Utille et al, Holzforschung, 57 266 (2003).

3. J.C. Dean, P.S. Walsh, B. Biswas et al, Chem. Sci., 5 1940 (2014).

FP1306 COST Action



9


Toward Carbon Fibers from Single Component Kraft Lignin Systems;Optimization of

Chain Extension Chemistry

Dimitris S. Argyropoulos*, Hasan Sadeghifar, S. Sen and Shradha Organic Chemistry of Wood Components Laboratory, Departments of Forest Biomaterials1 and Chemistry2,

North Carolina StateUniversity, Raleigh, 27695-8005, North Carolina,USA

* [email protected]

Abstract

Single component softwood kraft lignins have been sought after as precursors to carbon fibers. This noble goal

can be achieved by adding carbon onto lignin via propargylation. The reactivity of propargylated lignins may

then be modulated via methylation thus eliminating the onset of gelation via phenoxyl radical initiated random

polymerization. This paper demonstrates that properly installed, propargyl groups of an acetone soluble kraft

lignin (ASKL) fraction can be thermally polymerized to high molecular weights in a controlled manner. In order

to create single component chain extended softwood kraft lignin systems for carbon fiber applications, one needs

toregulate the amount and the positioning of the propargyl groups on the lignin. This became possible and it is

now demonstrated that the propargylation of lignin needs to occur first, followed by methylation and not the

other way around. Such a sequence offers substantial benefits for the onset of a Claisen rearrangement to occur

between the propargyl groups and the free C5 positions of the softwood lignin. Furthermore, once in position,

the created benzopyrans can effectively further polymerize in a controlled manner offering chain extended kraft

lignin products of sufficient molecular weight so as to apply subsequent stabilization and carbonization steps to

it.

Introduction

In our earlier effort we have embarked in describing and discussing the importance of propargylation

chemistry on lignin so as to synthesize lignin macromonomers for thermal polymerization via Claisen

rearrangement 1, 2

. We have also discussed that the molecular weight and glass transition temperatures of the

thermally polymerized lignin improves significantly relative to the starting material. The intricate polymer

structure created within lignin as a result of the benzopyran double bond thermal polymerization chemistry (see

Scheme 1 C) is offering a regular covalently linked framework from which, after carbonization, a regular carbon

fiber material could be envisaged to emerge. As such, thermally polymerized propargylated softwood lignin can

be explored as a prospective material for the synthesis of bio-based CF precursors.

Scheme 1. The sequence of reactions that involves lignin propargylation (A) followed by Claisen rearrangement

(B) and thermal polymerization (C)


Various reactivity considerations that are to be discussed in the presentation 3 were addressed by a series of

experiments where initially Acetone Soluble Kraft Lignin (ASKL) was propargylated, thus occupying all readily

accessible and highly reactive phenolic–OHs, followed by methylation of the remaining phenolic OH’s to limit

mailto:[email protected]

FP1306 COST Action



10


phenoxy radical induced thermal polymerization. All the polymerization reactions were conducted by heating the

samples at 180 °C for three hours and the corresponding molecular weights and distributions were determined.

As anticipated, the installation of the propargyl groups in more reactive positions, more readily prone to

Claisen rearrnagnent and thermal polymerization events, offered much better developed molecular

weights. The shape of the overall plot in Figure 1 is exponential, indicative of molecular weights

exceeding 130,000 g/mol at the extreme end of active propargyl group content (2.6 mmol/g). Similarly,

the extreme heterogeneity of the sample as evidenced by the ratio of Mw/Mn approaching nearly a value

of 50, is an undisputed indication that gelation statistics are operational. The fact that all thermally

polymerized samples were soluble in acetone and/or DMSO, indicates that using the specific starting

sample of ASKL (Mw of about 4,000g/mol) and within the examined range of active propargyl groups

(0.4-2.6 mmol/g), the reaction conditions were such that the gel point had not yet been reached or

exceeded. Overall, our experiments validate our contention that both gelation statistics and significant

reactivity issues are the underlying considerations that define the progress of thermally induced

polymerization chemistry on propargylated lignin samples.

Figure 1. Effect of active propargyl group on molecular weight and polydispersity of ASKL at 180 °C for three

hours of reaction for samples that were propargylated first prior to methylation3.

Conclusions

In this effort, an in-depth investigation of propargylation chemistry followed by a thermally induced Claisen

rearrangement on fractionated softwood kraft lignin is reported. In this study, the phenolic-OHs of acetone

soluble kraft lignin (ASKL) fractions are propargylated in basic media using variable amounts of propargyl

bromide, arriving at thoroughly characterized lignins with various degrees of substitution. Then, efforts towards

inducing a thermal-mediated Claisen rearrangement reaction (Scheme 1B) and the ensuing thermal

polymerization chemistry (Scheme 1C) of the pendant alkynes are described.2,3

As anticipated, the

multifunctional nature of the lignin causes it to arrive at a hyper-branched and cross-linked polymer, which is

intractable and not suitable for further thermoplastic processing. This major limitation is addressed by

appropriately reducing the degree of propargylation and masking the remaining phenolic−OHs by alkaline

methylation with dimethyl sulfate. This is a novel approach for the simultaneous systematic modulation of the

functionality and the reactivity of lignin developed in earlier parts of our work2.

References

1. Sen, S.; Sadeghifar, H.; Argyropoulos, D. S.: Kraft Lignin Chain Extension Chemistry via Propargylation, Oxidative

Coupling, and Claisen Rearrangement. Biomacromolecules 2013, 14, 3399-3408R.

2. Argyropoulos, D. S.: High Value Lignin Derivatives, Polymers, & Copolymers & Use Thereof in Thermoplastic,

Thermoset, Composite and Carbon Fiber Applications. Patent, US 20130255216 A1 2013.

3. Sadeghifar, H. Sen, S., Patil, S. V. ,Argyropoulos, D. S. , “TowardCarbon Fibers from Single Component Kraft Lignin

Systems; Optimization of Chain Extension Chemistry’ ACS Sustainable Chemistry & Engineering, DOI

10.1021/acssuschemeng.6b00848, June 2016.

0

5

10

15

20

25

30

35

40

45

50

0

20

40

60

80

100

120

140

0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3

Mo

lecu

lar

wei

gh

t, M

w (

mo

l/g

) x

10

00

Active propargyl groups (mmol/g)

Po

lyd

isp

ersi

ty (

PD

I)

Polydispersity (PDI)

Molecular Weight

FP1306 COST Action



11


Vanadium catalyzed aerobic oxidative processes for lignin degradation

E. Amadio, C. Zonta, G. Licini*

Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131, Padova, Italy

*[email protected]

Introduction

In the near future major changes are expected in the chemical industry regarding the use of raw

materials. As petroleum becomes less accessible, biomass-based carbon sources have emerged as potential

feedstocks for fuel production and commodity chemical manufacturing. Among the different sources,

lignocellulosic biomasses represent one of the most attractive and renewable carbon feedstocks. Due to its highly

aromativ and functionalized content, Lignin could be an ideal source of simple aromatic or fine chemicals.

However, the principal challenge in lignin valorisation arises from its complex chemical structure and inertness.

[1]. Herein, we will report on the reactivity of vanadium(V) homogeneous catalysts, bearing aminotriphenolate

ligands,[2] which have been found to be effective in the aerobic carbon-carbon cleavage of vicinal diols3 and less

reactive Lignin models (alpha-hydroxy ethers) with catalyst loading down to 0,01% and 8200 TONs.[3]

Experimental

The reactions have been performed in air or O2 atmosphere (1 atm), in organic solvents. Chemical yields have

been quantified by 1H NMR, GC or HPLC analysis. Reagents, when not commercially available, have been

synthetized following literature procedures.


In this communication we will present out most recent results related to the optimization of the V(V) catalyzed

aerobic oxidative degradation of lignin models (1,2-diols and alpha-hydroxy ethers)

In particular, under mild reaction conditions (organic solvents, rt-100°C, air/O2, 1 atm) the exclusive or

preferential C-C cleavage has been obtained with TONs up to 8200 and catalyst loadings up to 0.01%).

Preliminary results related to the reaction mechanism (metal species involved in the process, catalyst stability

under turn-over conditions, O2 activation, SET reactions) will be also described.

Acknowledgements

The authors acknowledge the Università di Padova for funding [Assegni Senior 2014, GRIC141OVJ. (E. A.

fellowship) and Networking 2014/2015].

References

1. C. Li, X. Zhao, A. Wang, G. W. Huber, T. Zhang Chem. Rev., 115, 11559 (2015); E. Amadio, R. Di Lorenzo, C.

Zonta, G. Licini Coord. Chem. Rev. 301-302, 147 (2015); K. S. Hanson, R. T. Baker, Acc. Chem. Res. 48, 2037-2048

(2015).

2. M. Mba, M. Pontini, S. Lovat, C. Zonta, G. Bernardinelli, E.P. Kündig, G. Licini, G. Inorg. Chem. 2008, 47, 8616

(2008); M. Kol, M. Shamis, I. Goldberg, Z. Goldschmidt, A. Sima, E. Hayut-Salant Inorg. Chem. Commun. 4, 177

(2001).

3. E. Amadio, B. Gjoka, C. Zonta, G. Licini submitted.

FP1306 COST Action



12


Electrochemical Conversion of Lignin – A Promising Approach to Obtain Value Added

Products?

T. Höfler, P. Neu, M. Mittelbach, S. Schober* Institute of Chemistry, Working Group “Chemistry and Technology of Renewable Resources”, Graz University,

Heinrichstrasse 28, A-8010 Graz Austria

Lignin as feedstock has become of increasing importance during the last decade. The idea was/is to obtain value

added products suitable as building blocks for chemical industry. But not only lignin itself is of interest. Many

efforts have been taken to directly convert lignin containing waste streams like weak or black liquor from paper

industry in order to achieve additional earnings by simultaneously reducing waste.

The here presented approach deals with lignin depolymerization trials via electrochemical treatment.

Investigations were carried out with neat lignins as well as direct treatment of weak-liquors. The

samples/solutions were treated at different voltages and samples were taken out regularly to follow conversion

over time. As analytical parameters in the first stage, pH, conductivity, chemical oxygen demand, FT-IR

characteristics and molecular weight distributions were analyzed. In a second step, molecular characteristics of

the “depolymerized” material will be investigated by GC/MS and HPLC/TOF-MS. Additionally sulfur and

sodium contents are measured to evaluate the behavior of former -S-S-interlinked or sulonic acid groups and

sodium sulfonates

As the results showed, a significant part of the lignin is converted into lower molecular weight compounds.

Decreases in molecular weight, CSB, pH and conductivity are observed. Details on the results will be presented

as well as findings on species formed during degradation. As these investigations are currently in process, no

further details can be given in this abstract unfortunately.

FP1306 COST Action



13


Catalytic fast pyrolysis of various types of lignin: effect of isolation method, biomass

source and biomass pretreatment

P. Lazaridis1, C. Nitsos

2, L. Matsakas

2, U. Rova

2, P. Christakopoulos

2, K. Triantafyllidis

1,3*

1Department of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; 2Department of Civil, Environmental & Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå,

Sweden, 3Chemical Process and Energy Resources Institute, CERTH, 57001 Thessaloniki, Greece

*e-mail: [email protected]

Introduction

Despite the high potential of lignin as a raw material for the fuel (liquid) and chemical industry, it is still under-

utilized compared to the carbohydrate fractions of biomass. The effectiveness of the various lignin valorization

processes (i.e. catalytic hydrogenolysis, catalytic oxidation, catalytic fast pyrolysis, gasification) depends greatly

on the structure, composition, integrity, MW and other physical and chemical properties of lignin, which in turn

are affected by the source of biomass and the type of pretreatment/process used for lignin isolation [1]. In the

present work, we show the potential of non-catalytic and catalytic fast pyrolysis of lignin towards the production

of bio-oil rich in mono-phenolics and/or mono-aromatics for various possible down-stream utilization options

(i.e. production of resins, extraction of BTX aromatics, alkane fuel via HDO, etc.). Furthermore, we investigate

the effect of lignin type, with respect to the various parameters mentioned above (biomass source, pretreatment

of biomass, method of isolation).

Experimental

The biomass sources used include commercial beech wood (Lignocel), olive tree pruning, vineyard pruning and

almond shells. Three types of lignin were studied: typical kraft type lignin (commercial, Sigma-Aldrich),

organosolv lignin from beech wood, and hydrolysis lignin from olive tree and grapevine prunings and almond

shells. In the case of hydrolysis lignin, the biomass samples were initially pretreated by hydrothermal, dilute acid

and steam explosion methods, which resulted in the removal of hemicellulose from the solids. The pretreated

materials were subjected to enzymatic hydrolysis to release glucose for subsequent fermentation to ethanol. The

lignin-enriched residuals following polysaccharide deconstruction and fermentation were used for the fast

pyrolysis experiments. The fast pyrolysis experiments were performed on a Pyrolyzer/Gas Chromatography-

Mass Spectrometry (Py/GC-MS) instrument (Frontiers & Shimadzu), at 400-600oC, with or without the use of

various acidic zeolite catalysts, such as H-ZSM-5, USY, Beta, etc.


The representative results in Figure 1 show that the non-catalytic, thermal fast pyrolysis of the beech-wood

lignin recovered via organosolv process provides a bio-oil with more than 70 % useful low molecular weight

phenolics. Such a bio-oil can be used in polymer-

resin production. On the other hand, when a

strongly acidic zeolite is used as catalyst, the bio-oil

contains both phenolics and small mono-aromatics,

and can be additionally utilized as source of BTX

aromatics for the chemical industry.

Figure 1. Composition of thermal and catalytic

bio-oil produced by fast pyrolysis of beech-wood

lignin recovered via organosolv extraction

Acknowledgements

This research has been partially co-financed by EU (ESF) and Greek national funds through Operational

Program "Education & Lifelong Learning" of NSRF-Action: Aristeia II (HierZeo4Biofuel). It was also partially

supported by COST (European Cooperation in Science and Technology) Action FP1306 via a Short Term

Scientific Mission of Dr. Christos Nitsos at Luleå University of Technology, and Bio4Energy, a strategic

research environment appointed by the Swedish government.

References [1] R. Rinaldi et. al., Angew. Chem., 55, 2–54, (2016).

FP1306 COST Action



14


Study of the influence of zeolite and lignin type on the lignin pyrolysis products

Jelena Milovanović1*

, Rafael Luque2, Roman Tschentscher

3, Antonio A. Romero

2, Hangkong Li

4, Kaimin Shih

4

and Nevenka Rajić5

1Innovation Centre of the Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade,

Serbia; 2Departamento de Química Orgánica, Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie (C-3),

Ctra Nnal IV, Km 396, E-14014 Córdoba, Spain; 3SINTEF, Forskningsveien 1, 0314 Oslo, Norway; 4Department of Civil Engineering, University of Hong Kong, Pokfulam Road, Hong Kong; 5Faculty of Technology and

Metallurgy, University of Belgrade, Karnegijeva 4, 11120 Belgrade, Serbia

*e-mail: [email protected]

Introduction

The bio-oils obtained from lignin pyrolysis generally contain a large amount of oxygen-containing products and

small amount of aromatic compounds. Accordingly, such bio-oils are corrosive, viscous and unstable and require

further upgrading. Zeolites ZSM-5, BETA and Y have been reported as promising for softwood pyrolysis since

they decrease the yield of oxygen-containing products and increase the yield of desirable aromatic compounds

[1]. The present investigation was aimed to study NiO-containing zeolites (H-ZSM-5, H-BETA and H-Y) in the

catalytic pyrolysis of Eucalyptus (EUC) and Hardwood lignin (HL).

Experimental

NiO/H-ZSM-5, NiO/H-BETA and NiO/H-Y were prepared by mechanochemical dry milling (MCDM) method

[2]. The pyrolysis of EUC and HL were examined at 500 °C under N2. GC and GC-MS were used to characterize

pyrolysis products.


All studied catalysts increased the yield of aromatics and decreased the yield of oxygenates as compared to non-

catalytic experiment for both lignin types. However, the catalytic activities are affected by zeolite structural

features and by lignin type. The highest liquid and gas yield, and lowest coke was obtained with NiO/H-Y which

also increased the amounts of desirable and decreased undesirable pyrolysis products. NiO/H-ZSM-5 gave the

bio-oil with the highest amount of aromatics and the lowest amounts of oxygenates but it exhibits a low

selectivity towards PAHs. A high yield of hydrogen was obtained with NiO/H-Y indicating a synergetic catalytic

activity of NiO particles and H-Y.

Conclusions

The NiO-containing catalysts (H-ZSM-5, H-BETA and H-Y) prepared by MCDM method exhibit large specific

surface areas and the presence of mainly Brönsted acid sites. The products obtained by an intermediate fast

pyrolysis showed a dependence on both zeolite structural features and lignin origins suggesting HL as a more

suitable feedstock.

Acknowledgements

The authors gratefully acknowledges the financial support of COST Action FP1306, BRISK- Biofuels Research

Infrastructure for Sharing Knowledge, Ministry of Education, Science and Technological Development of the

Republic of Serbia (172018) as well as the Norwegian Research Council (Idealab project Capture and

Infrastructure project NorBiolab) and Innventia AB for lignin samples.

References

1. Y. Yu, X. Li, L. Su, Y. Zhang, Y. Wang, H. Zhang, 2012. Appl. Catal. A Gen. 447-448, 115 (2012).

2. J. Milovanovic, N. Rajic, A. A. Romero, H. Li, K. Shih, R. Tschentscher, R. Luque, ACS Sustain. Chem. Eng.

(10.1021/acssuschemeng.6b00825).

FP1306 COST Action



15


High throughput single stage continuous hydrodeoxygenation of liquid phase pyrolysis oil

Nikolaus Schwaiger1, Roland Nagl

1, Klaus Schlackl

1, Klara Treusch

2, Thomas Pichler

1, Manuel Menapace

1,

Dominik Heinrich1, Manuel Tandl

1, Anna Mauerhofer

1, Peter Pucher

2, Matthäus Siebenhofer

1

1Graz University of Technology, Institute of Chemical Engineering and Environmental Technology, Graz, Austria,2BDI-

BioEnergy International AG, Grambach/Graz, Austria

Introduction Non-renewable energy resources such as oil and coal will not suffice the increasing demand of energy in the

future. To fill the upcoming gap a biomass liquefaction concept has been developed. This concept consists of

two main process steps. In the first step lignocellulosic biomass is converted into pyrolysis oil and pyrolysis char

through the bioCRACK process1. The bioCRACK process was successfully operated in pilot scale (100 kg/h

lignocellulosic feed) over a period of two years. In the second step the intermediate product liquid phase

pyrolysis oil is upgraded by hydrodeoxygenation (HDO)2. Classic HDO processes for fast pyrolysis oil

beneficiation propose low liquid hourly space velocity (LHSV) of 0.1-0.5 [h-1

] and two-step hydrotreating to

avoid plugging and catalyst deactivation3,4

. Feasibility of these techniques in standard refineries is hardly

achievable and does cause huge investment cost for industrial scale application. For co-processing of pyrolysis

oils and fossil fuel intermediates higher LHSV rates are desired.

Experimental Liquid phase pyrolysis oil was upgraded by continuous hydrodeoxygenation in lab scale. Hydrotreatment was

performed catalytically in a plug flow reactor. Operation parameters were 400°C and 121 bar hydrogen pressure.

LHSV was varied between 0.5 and 3. Catalysis was provided by a sulfidised metal oxide. Experiment duration

was 50 h for each experiment. After HDO of liquid phase pyrolysis oil 2 liquid product phases were collected.

Results and Discussion According to the data in Table 1 LHSV rates between 0.5 [h

-1] and 2 [h

-1] didn´t show heavy impact on the HDO

results of liquid phase pyrolysis oil quality. Carbon transfer from the feed was slightly rising from 44.7% to

45.9% and finally to 47.0%. Water content of the product phase was close to 0. At a LHSV of 2 [h-1

]

hydrodeoxygenation rate was decreasing and an oxygen content of 1.3% was detected. The slightly higher

oxygen content originates in a little higher water content of 0.13%. At a space velocity of 3 [h-1

] unsteady

operating conditions, like irregular pressure changes, were observed.

Table 1: Elemental composition and oxygen content of the organic phase

50h HDO treatment LHSV[h-1

] Water content C [%] H [%] Rest = O [%] N [%]

Organic phase 0.5 0.02% 86.6% 12.9% 0.0% 0.4%

Organic phase 1 0.01% 85.9% 13.6% 0.0% 0.5%

Organic phase 2 0.13% 85.4% 12.9% 1.3% 0.4%

Conclusions

It was shown that space velocities from 0.5 to 2 [h-1

] are applicable for the production of biofuels out of liquid

phase pyrolysis oil. Neither product quality nor carbon transfer into the fuel fraction suffer from less residence

time. The fuel output can be raised with higher LHSV rates due to lower hydrocarbon cracking.

Acknowledgements

This work was funded by the Austrian Research Promotion Agency (FFG) under the scope of the Austrian

Climate and Energy Fund

References

1 N. Schwaiger, D. C. Elliott, J. Ritzberger, H. Wang, P. Pucher and M. Siebenhofer, Green Chem., 2015, 17, 2487–

2494.

2 H. Pucher, N. Schwaiger, R. Feiner, L. Ellmaier, P. Pucher, B. Chernev and M. Siebenhofer, Green Chemistry,

2015, 17, 1291–1298.

3 M. V. Olarte, A. H. Zacher, A. B. Padmaperuma, S. D. Burton, H. M. Job, T. L. Lemmon, M. S. Swita, L. J.

Rotness, G. N. Neuenschwander, J. G. Frye and D. C. Elliott, Topics in Catalysis, 2016, 59, 55–64.

4 D. C. Elliott, Energy & Fuels, 2007, 21, 1792–1815.

FP1306 COST Action



16


Lignin breaking down: Comparison between solid lignin and black liquor base catalyzed

depolymerization in order to produce phenolic compounds

Xabier Erdocia, Javier Fernández-Rodríguez, María González Alriols, Jalel Labidi* Chemical and Environmental Engineering Department, University of the Basque Country, Plaza Europa 1, San Sebastián,

Spain. *[email protected]

Introduction

Lignin is the second most abundant natural polymer made up by the combination of three different

phenylpropane monomer units: guaiacyl alcohol, p-coumaryl alcohol and syringyl alcohol. These phenylpropane

units form an amorphous three-dimensional structure and are linked mainly by an aryl-aryl ether linkage [1]. The

aromatic structure of the lignin, makes lignin a suitable candidate to be catalytically transformed into low

molecular weight phenolic compounds, which may substitute petroleum based compounds [2].

Experimental

Almond shell was used in this work as raw material. Firstly, an autohydrolysis pretreatment stage was carried

out to remove the major hemicelluloses content in the solid feedstock. Afterwards, soda process (dissolution of

NaOH (7.5 wt.%) at 121 ºC, 90 min and a solid:liquid ratio of 1:6) was employed to extract the lignin. Part of the

obtained black liquor was directly subjected to a high pressure and temperature process (300 ºC, 80 min and 20 g

of black liquor) in order to depolymerize the lignin dissolved in the liquor. On the other hand, lignin from black

liquor was isolated using selective precipitation methods and submitted to a depolymerization process using the

same conditions applied to the black liquor but employing a NaOH solution of 4% wt.% in a solid:liquid ratio of

1:20.


From both treatments, black liquor and solid lignin, three different products were obtained: oil, char and residual

lignin. Oil yield, which is the most interesting product containing phenolic compounds, was higher in case of the

black liquor. Furthermore, char production, most undesirable subproduct, was reduced in the case of soda black

liquor treatment.

Figure 1. Yields of the different products obtained after lignin and black liquor treatments.

Conclusions

The direct treatment of soda black liquor in order to depolymerize the dissolved lignin, gave better results

regarding to oil and char yields than depolymerizing the isolated solid lignin. In addition, the more simple

treatment of the black liquor makes it more suitable for lignin depolymerization.

Acknowledgements

The authors would like to thank the Spanish Ministry of Economy and Competitiveness (CTQ2013-41246-R)

and the University of the Basque Country (postdoctoral fellowship ESPDOC15/044) for funding.

References

1. F.S. Chakar, A.J. Ragauskas, Ind. Crops Prod., 20 131 (2004).

2. S. Cohen, P.A. Belinky, Y. Hadar, C.G. Dosoretz, Bioresour. Technol. 100(7) 2247 (2009).

FP1306 COST Action



17


Willow lignin oxidation and depolymerisation under low cost ionic liquid

R. Prado1*

, X. Erdocia2, G. F. De Gregorio

1, J. Labidi

2, T. Welton

1

1Department of Chemistry, Imperial College London, London SW7 2AZ, UK

2Chemical and Environmental Engineering Department, University of the Basque Country, San Sebastian, Spain

*[email protected]

Introduction

Lignin has a complex structure, so that, few investigations using lignin directly as a substrate have been

conducted to study its reactivity. However, many studies have been carried out using lignin model compounds in

order to elucidate the reaction mechanisms and the proper conditions to extend the reaction to lignin. The

depolymerisation of lignin model compounds and lignin in ionic liquids (ILs) have been studied under reductive

and oxidative conditions. The reductive conditions were achieved by adding Lewis and Brönsted acids as a

catalyst; however, these reactions were only briefly studied because of the low reactivity shown by lignin despite

the high yields obtained with lignin model compounds. Oxidation has been studied more extensively, in most

cases coupling a metal catalyst such as Fe, Mn, Co, V and an oxidizing agent such as O2 or H2O2 with many

different ILs under different conditions. The role of the ILs in this case was to be both the reaction solvent and/or

catalyst [1,2]. In this work the effect of H2O2 and TiO2 as catalyst for lignin oxidative depolymerisation were

tested.

Experimental

Willow biomass was subjected to different pretreatment [3] and oxidation conditions under either homogeneous

or heterogeneous catalysis, using H2O2 as oxidant and TiO2 as catalyst with triethyl amine hydrogen sulfate as

solvent [Et3NH][HSO4]. Lignin, residual lignin, oil and the recovered IL were characterized in order to

determine the effects of each treatment. The final ionic liquid was characterized in order to determine its

suitability to be reutilized.


Lignin was successfully extracted and depolymerized by oxidation (Table1) and characterised by ATR-IR,

HPSEC, py-GCMS. The average molecular weight (Mw) of lignin decreased with the oxidant treatment for all

the pretreatment conditions. By the spectroscopic characterisation it was found that lignin was oxidised by the

action of H2O2 and TiO2. The chromatographic characterisation showed evidence of lignin oxidation after the

treatment, it was also observed that the phenolic part was highly degraded for TiO2 treatment, on the other hand

for H2O2 sugar part was the most degraded. Table 1. Reaction yields.

Sample Lignin % Oil % S/G Mw

Lig 2 20 ± 1 2.16±0.08 19,744

Lig 2 H2O2 7.6 ± 0.4 15.9 ± 0.6 1.62 13,041

Lig 2 TiO2 2.6 ± 1 22.3 ± 0.4 1.71 10,622

Lig 8 19.7± 0.3 2.2±0.1 24,555

Lig 8 H2O2 6.3 ± 0.4 14.9 ± 0.8 1.71 9,820

Lig 8 TiO2 5.4 ± 0.1 16.3 ± 0.7 1.83 13,612

Lig 22 20.1 ± 0.6 2.26±0.06 35,111

Lig 22 H2O2 5.35 ±0.05 6.9 ± 0.2 1.18 8,463

Lig 22 TiO2 2 ± 1 11.10 ±0.7 1.16 5,028

The obtained oil was characterised by GCMS, it was composed mainly of acids derived from the sugar and

lignin fractions, the TiO2 showed oils richer on phenolic derived compounds than sugar fractions.

Conclusions

Lignin was successfully depolymerised by using TiO2 as catalyst lead to have oils richer on phenolic derived

compounds. The IL was clean after the oxidant treatment, ready for being reused.

References

1. George, K. Tran, T. J. Morgan, P. I. Benke, C. Berrueco, E. Lorente, B. C.Wu, J. D. Keasling, B. A. Simmonsa, B. M.

Holmes. Green Chem. 13, 3375-3385 (2011).

2. G. Chatel, R. D. Rogers, ACS Sustainable Chem. Eng. 2 (3), 322–339 (2013).

3. R. Prado, A. Brandt, X. Erdocia, J. Hallet, T. Welton, J. Labidi, Green Chem. 18, 834-841 (2016).

FP1306 COST Action



18


Valorization of an invasive wood species by lignin extraction with low environmental

impact solvents

M. Graça V.S. Carvalho*, Ana R. Fernandes, Jorge M.S. Rocha and Abel G. Ferreira

CIEPQPF, Department of Chemical Engineering, University of Coimbra, R. Sílvio Lima, Pólo II, 3030-790 Coimbra,

Portugal, *[email protected]

Introduction

The wood of mimosa tree (Acacia dealbata) has no commercial use, being an invasive species in many habitats,

with great resistance and ease of propagation. Deep eutectic solvents/low transition temperature mixtures

(DES/LTTMs) have recently been proposed as a new generation of green designed and more environmentally

friendly solvents for the deconstruction of lignocellulosic biomass [1]. These solvents consist of two compounds,

one donor and one acceptor of hydrogen bonds. Previous studies on mimosa wood had shown that

glycerol/potassium carbonate mixture [G-PC] and liquids composed by 2-chloroethyltrimethylammonium

chloride and lactic acid [LA-CETMAC] were selective for lignin, which envisages a very interesting valorization

of this invasive species [2].

Experimental

Mimosa (Acacia dealbata) with lignin, cellulose and pentosan content of 27, 42 and 19%. Chemicals were

purchased from Sigma. CellicCTec2 was kindly provided by Novozymes. 10 g of [G-PC], molar ratio from 20:1

to 200:1, or [LA-CETMAC], molar ratio 5:1 to 10:1, was mixed with 0.5 g of sawdust (size fraction 0.25-0.50

mm) at the testing temperature (80 or 65ºC) up to 16 h. The undissolved solid material obtained after the

addition of ethanol, centrifugation, water washing and drying was analyzed for total lignin (Tappi T222 and UM

250) and monosaccharides composition (by HPLC, with a refractive index detector, Aminex column HPX-87P).


For the [G-PC] mixtures, higher wood dissolution yields (~17%) were obtained with lower molar ratios (20:1

and 50:1), probably due to increasing viscosity. About one half was caused by lignin dissolution. The use of two

sequential treatment cycles increased the global dissolution yield to ~20% but the selectivity towards lignin

diminished. The dissolution kinetics can be seen in Fig.1. Although wood and lignin dissolution yields increased

with time, the highest selectivity was achieved for 10h. Cellic CTec2 (25 FPU.g-1

) can digest 90% of the solid

material treated with [G-PC] mixtures.

Figure 1. Wood and lignin dissolution yields (wood basis) for mimosa sawdust in [G-PC 50:1] mixture at 80ºC.

For the [LA-CETMAC] mixture, lower yields were obtained (6 to 10%), but with higher selectivity (~90% was

lignin). Yield increased with molar ratio of LA (5 to 10:1) or with temperature (65 to 80ºC), mainly due to

higher carbohydrates dissolution rate. The loss of selectivity was also observed when two sequential treatment

cycles were performed. Cellic CTec2 (25 FPU.g-1

) can only digest 60% of the solid material treated with [LA-

CETMAC] mixture.

References

1. M. Francisco, A. Bruinhorst, M. Kroon, Green Chem.,14, 2153-2157 (2012)

2. M.G.V.S. Carvalho, F.M.R. Afonso, T.S.N. Marques, J.M.S. Rocha, A.G.M. Ferreira, XXIII TECNICELPA -

International Forest, Pulp and Paper Conference, Porto (2016)

FP1306 COST Action



19


Selective transformations of biomass-derived organic compounds using heterogeneous

photocatalysis

Agnieszka Magdziarz1, Juan C. Colmenares

1*

Institute of Physical Chemistry PAS, Kasprzaka 44/52, 01-224 Warsaw, Poland

* [email protected]

Introduction

The use of heterogeneous photocatalysis in the selective oxidation processes could be a successful replacement

of traditional oxidation methods by new "green" routes for chemicals production. It seems to be extremely

interesting and useful from the point of view of the selective valorization of biomass-derived residues [1].

Lignocellulose, which is an easy reached source of biomass, would be a good substrate for different

transformations into valuable chemicals and platform molecules [2]. The aim of this work is to study the

selective photocatalytic transformations of lignocellulosic biomass-derived model compounds into valuable

chemicals: a) photo-oxidation of aromatic alcohols into aldehydes b) photo-oxidation of sugars into carboxylic

acids.

Experimental

Iron-containing TiO2 -based photocatalysts, prepared by different ultrasound-assisted methods, were studied in

these reactions. The photocatalyst used in the photo-oxidation of glucose was prepared by ultrasound-assisted

wet impregnation method [3]. The sonophotodeposition method was applied in the synthesis of the photocatalyst

for the photo-oxidation of benzyl alcohol [4]. Selective glucose oxidation was performed under UV light

whereas selective oxidation of benzyl alcohol was carried out under UV-vis lamp.


Among all tested photocatalysts iron-containing TiO2 photocatalyst supported on zeolite Y resulted to be the

most selective material in the partial glucose photo-oxidation into gluconic and glucaric acids. After 20 min of

UV-light illumination achieved 94.3% of selectivity in the liquid phase in 50%H2O/50%ACN solvent

composition. The acidic character of the zeolite support could facilitate the selectivity of this reaction. A drop in

glucose conversion observed with increasing amount of water in the solvent mixture, could be explained by the

competition of water and glucose for the adsorption sites of the photocatalyst. In the photo-oxidation of benzyl

alcohol into benzaldehyde higher alcohol conversion and yield of benzaldehyde was obtained for the iron-

containing photocatalyst prepared by the sonophotodeposition method in comparison with the iron-free

photocatalyst. This behaviour could be correlated with better properties of the photocatalyst obtained in the

procedure of sonophotodeposition, especially better absorption properties in the visible range.

Conclusions

Iron incorporation helps to obtain more efficient systems for selective photo-oxidation processes. It has been

observed that parameters such as solvent composition and illumination time considerably affect the selectivity of

the photo-oxidation of glucose. Combination of photo- and sonochemistry in sonophotodepotion method has a

positive effect on the properties of materials prepared using this method.

Acknowledgements

This research was partially supported by the National Science Centre (NCN) in Poland within research project

2013/11/N/ST5/01923. Prof. Dr. Juan C. Colmenares gratefully acknowledges support from COST Action

FP1306 for networking and possibilities for meetings and future students exchange.

References

1. J.C. Colmenares, R. Luque, Chem. Soc. Rev. 43 765 (2014)

2. M. Stocker, Angew. Chem. Int. Ed. 47 9200 (2008)

3. J.C. Colmenares, A. Magdziarz, O. Chernyayeva, D. Lisovytskiy, K. Kurzydlowski, J. Grzonka, ChemCatChem, 5

2270 (2013)

4. A.Magdziarz, J.C. Colmenares, O. Chernyayeva, K. Kurzydlowski, J. Grzonka, ChemCatChem, 8 536 (2016)


FP1306 COST Action



20


Impact of lignin properties on maximum achievable monomer yields for C-O cleaving

lignin depolymerization approaches

Thanaphong Phongpreecha1, Nicholas Hool

1, Kendall Christy

1, David Hodge

1,2,3*

1 Department of Chemical Engineering & Materials Science, Michigan State University, East Lansing, Michigan, USA 2 Department of Biosystems & Agricultural Engineering, Michigan State University, East Lansing, Michigan, USA

3Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden

*[email protected]

Introduction

Despite comprising a substantial portion of plant cell walls, the chemical functionality in process lignins

generated in pretreatment or fractionation processes remains unutilized with this fraction typically targeted as a

low-value fuel for process heat and power. As such lignin may offer the opportunity to serve as a feedstock for

the production of aromatic products if feasible conversion pathways can be developed that are able to be

integrated into conversion pathways for biomass fractionation, deconstruction, or conversion. However, well-

established challenges to utilization of lignins include its heterogeneity, the decreased reactivity to various

chemistries employed for valorization of process lignins relative to native lignins, and the generation of a

distribution of products resulting in separations challenges [1, 2]. Thus, an important need is to generate less

heterogeneous lignins with higher reactivity and the need to understand lignin processing behavior.

Experimental

Motivated by this need, in this work we (1) fractionate hardwood alkali lignins utilizing two approaches to

reduce lignin heterogeneity and to generate fractions enriched or depleted in select properties, (2) relate lignin

properties (β-aryl ether content, S/G ratio, molar mass, phenolic hydroxyl content) to fractionation behavior, (3)

use a diverse range of fractionated process lignins or native lignins to relate lignin properties to the aromatic

monomer yield using three catalytic depolymerization approaches (thioacidolysis, catalytic oxidation, and

catalytic hydrogenolysis), and (4) understand lignin properties contributing to the maximum possible monomer

yields using these catalytic depolymerization approaches.


We were able to demonstrate strong clear correlations between many lignin properties and the phase partitioning

behavior in the alkaline hardwood lignins. Furthermore, we outline for the first time a rational approach for

estimating the maximum theoretical monomer yields in lignin from C-O cleavage based on β-aryl ether content

and furthermore demonstrate that experimental values from thioacidolysis follow the same trend as the predicted

values for yields. Notably, utilizing lignins with high β-aryl ether content that are not substantially modified

during pretreatment, it is possible to achieve aromatic monomer yields >50% using C–O cleaving approaches.

Conclusions

In this work, we were able to demonstrate both a clear relationship between alkaline hardwood lignin properties

and their phase partitioning behavior and furthermore link the lignin β-aryl ether contents to the maximum

achievable monomer yields utilizing several C-O cleaving approaching.

Acknowledgements

This work was funded by the U.S. Department of Agriculture Northeast Sungrant Initiative.

References

1. PCA Bruijnincx, BM Weckhuysen, Nat. Chem. 6, 1035–1036 (2014).

2. JD Holladay, J Bozell, JF White, DK Johnson, Technical Report PNNL-16983 (2007).

FP1306 COST Action



21


Chemoenzymatic fractionation and characterization of pretreated birch outer bark

Anthi Karnaouri1,2

, Heiko Lange2, Claudia Crestini

2, Ulrika Rova

1 and Paul Christakopoulos

1*

1Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources

Engineering, Luleå University of Technology, Luleå, Sweden

2 University of Rome ‘Tor Vergata’, Department of Chemical Sciences and Technologies,

Via della Ricerca Scientifica, 00133 Rome, Italy

*[email protected]

Introduction

The total production of market pulp in Sweden amounts to approximately 3.8 million tons annually and leads to

the production of considerable amounts of birch bark as a residual product from log debarking, usually burned

for energy production. The bark and, in particular, its outer layers have been the subject of intensive research

because of their high content of compounds with wide beneficial chemistry and bioactivity, such as pentacyclic

lupine-type triterpenes and suberinic polyesters [1,2]. In order to improve the transformation of multiple biomass

feedstocks, better understanding of the extraction and biodegradation of these components is needed. The present

work is focused on the fractionation of birch bark by integrating different physicochemical pretreatment methods

[3] with enzymatic depolymerization and the evaluation of these treatments on the solid fractions retained.

Experimental

Untreated and steam exploded, hydrothermally and organosolv treated bark samples from birch (B. pendula)

were incubated with enzyme mixtures consisted of different types of carbohydrate-acting enzymes and esterases,

and the effect of enzymes was analyzed with 31

P NMR and {13

C-1H} HSQC. The suberin and lignin fractions

were isolated chemically and their properties were characterized by gas chromatography (GC-MS), 31

P NMR,

{13

C-1H} HSQC and gel permeation chromatography (GPC).


Ball-milling of the samples was crucial in order to obtain a homogeneous solution for structural characterization

of the polymers. Evaluation of cutinase activity on birch outer bark revealed that the enzymes perform the

cleavage of ester bonds resulting in reduction of methoxy and aliphatic groups in the remaining solid fraction,

while the aromatic fraction remains intact. It was demonstrated that the lignin fraction was enriched in guaiacyl

phenolics but still contained some associated aliphatic acids and carbohydrates, while the suberin fraction

presented a polymodal pattern of structures with different molecular weight distributions.

Conclusions 31

P NMR, {13

C-1H} HSQC and GPC analytical methods can be successfully applied for the evaluation of

structural changes on birch outer bark after physicochemical and enzymatic treatment. Treatment with esterases

led to cleavage of ester bonds and partial depolymerization of pretreated outer bark.

Acknowledgements

The present project is supported from KEMPE Foundations (SMK-1537) and through the strategic research

environment Bio4Energy. Anthi Karnaouri wishes to thank European COST Action FP1306 for funding a Short

Term Scientific mission to University TorVergata, Rome.

References

1. M.L. Mattinen, I. Filpponen, R. Järvinen, B. Li, H. Kallio, P. Lehtinen, D. Argyropoulos, J. Agric. Food Chemistry,

57, 9747 (2009).

2. J. Rizhikovs, J. Zandersons, G. Dobele, A. Paze, Ind. Crop. Prod. 76, 209 (2015).

3. A.Karnaouri, U. Rova, P. Christakopoulos, Molecules, 21, 4 (2016).

birch outer bark

aromatic region

aliphatic region

FP1306 COST Action



22


Applications of laccase treatments to modify lignin properties

Anna Kalliola*, Martta Asikainen, Taina Ohra-aho and Tarja Tamminen VTT Technical Centre of Finland Ltd, Espoo, Finland

*[email protected]

Introduction

The potential of lignin in material applications, such as in composites, is being actively investigated. However,

there are several difficulties in applying lignin. One of them is the volatile organic compounds (VOCs), either

present in technical lignin, or formed as they are processed at high temperatures in thermoplastic processes. The

other problem is the poor melt-flow, meaning the softening behavior of lignin under the elevated temperatures.

Laccase-catalyzed O2 oxidation was applied to polymerize lignin-derived low-molecular phenolics for the

reduction of VOCs [1]. It was also intended to introduce phenolic derivatives with a polyether-type hydrophilic

side chain into the lignin structure in order to soften the lignin [2]. In these studies, oxidation by O2 under

alkaline conditions was investigated as an alternative method to induce polymerization of phenolics in an

analogous manner to the laccase-catalyzed reaction, via the phenoxyl radicals. Alkaline conditions also enable

lignin dissolution and thus modification in high concentrations.

Experimental

Three fungal laccases, ThL (from Trametes hirsuta), TaLcc1, and TaLcc2 (from Thielavia arenaria), active

under acidic conditions, were used for softwood kraft lignin treatments. To increase the dissolution and the

reactivity of lignin, a fungal laccase r-MaL (from Melanocarpus albomyces), functioning at pH 8, was also

evaluated. For lignin functionalization, hydrophilic derivatives, vanillic acid PEG methyl ester and ether were

synthesized and applied. Alkaline SEC was used to follow the changes in lignin molar mass. Lignin odor was

rated by sensing analysis. Thermal desorption (TD-GC/MS) method was developed to determine volatile

degradation products of lignin at temperatures prevailing in thermoplastic processing [1, 2].


All laccase treatments were found to increase kraft lignin molar mass to some extent. According to sensing

analysis, undesirable odor in kraft lignin suspension could be reduced to a greater extent by alkali-catalyzed than

by laccase-catalyzed O2 oxidation. According to thermal desorption analysis, besides the reduction of guaiacol,

the main degradation product of lignin, alkali-O2 oxidation also reduced the amount of sulfur containing VOCs.

However, the odor threshold values of the main VOC compounds are extremely low, in the range of ppb, which

poses a challenge to VOC reduction [1]. Kraft lignin functionalization with a hydrophilic phenolic compound

was tried to lower the glass transition temperature (Tg) of lignin. Unfortunately, homogeneous polymerization of

this compound was favored over coupling to lignin. Efficient lignin polymerization under alkali-O2 conditions

with high lignin concentration (25 w-%) could also be obtained [2]. Especially linear, native like lignin, has a

great tendency to adsorb on surfaces and thus cause fouling followed by flux decrease during membrane

filtration of biorefinery extracts. Laccase-catalyzed polymerization changes the physicochemical state of lignin

and is thus expected to reduce its stickiness as the linearity decreases. Thus, laccase oxidation may decrease

lignin tendency to foul membranes. This hypothesis is tested in an on-going study where laccase, e.g. ThL, is

introduced in membrane installation (on spacer) used for filtrating hot water extract of birch chips.

Conclusions

Laccase catalyzed O2 oxidation for lignin polymerization is suitable for applications where lignin exists under

acidic condition and polymerization by alkali catalyzed O2 oxidation cannot be considered. Next, laccases will

be tested to reduce lignin fouling during membrane filtration of hot water extract of birch chips.

Acknowledgements

Finnish Academy is thanked for financial support (project CatMe – Catalytic membranes for decreasing of lignin

originated fouling).

References

1. A. Kalliola, A. Savolainen, G. Faccio, T. Ohra-aho, T. Tamminen, BioResources, 7 2871 (2012)

2. A. Kalliola, M. Asikainen, R. Talja, T. Tamminen, BioResources, 9 7336 (2014)

FP1306 COST Action



23


Directed evolution of bacterial lignolytic enzymes

Vânia Brissos, Diogo Tavares, Mara Marques, Sónia Mendes and Lígia O. Martins*

Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Ava da República, 2780-901

Oeiras, Portugal

*[email protected]

In recent years we have successfully established a research program focused on the investigation of fundamental

and technological aspects of bacterial oxidoreductive enzymes, laccases, metallo-oxidases, azo-quinone

oxidoreductases and DyP-peroxidases[1-3]. Research on structure-function characterisation revealed key aspects

of these enzymes such as the conformational and electrostatic interactions modulating the catalysis. Other

advances included the demonstration of the efficiency of these enzymes for degradation and detoxification of

industrial dyes and synthesis of aromatic added-value compounds [4-6]. Recently, laboratory directed evolution

approaches were established in order to increase the oxidative efficiency for aromatic compounds of the metallo-

oxidase McoA from the hyperthermophilic bacterium Aquifex aeolicus and the dye-decolourising peroxidase

PpDyP from Pseudomonas putida MET94 [7]. Four rounds of random mutagenesis of the mcoA-gene followed

by high-throughput screening (≈ 94,000 clones) led to the identification of the 2B3 variant featuring a 2-order of

magnitude higher efficiency for the typical laccase substrate ABTS (2,2’-azinobis-(3-ethyl-benzothiazoline-6-

sulfonic acid)) than the wild-type enzyme and showing additionally, a higher activity for phenolics and synthetic

aromatic dyes. Notably, the recombinant 2B3 variant, exhibited an enhanced solubility and thus a higher kinetic

and thermodynamic thermostability. 2B3 variant accumulated 15 mutations (5 silent) and, recently, DNA

shuffling of wild type and 2B3 genes followed by screening and DNA analysis allowed to distinguish 4

functional from 6 non-functional (neutral) mutations. These results in combination with the X-ray studies of

wild-type and variants allow discriminating the structural basis of the altered McoA substrate specificity and

increased thermostability. Three rounds of random mutagenesis of the gene coding for a bacterial DyP

peroxidase, PpDyP followed by high-throughput screening led to the identification of an evolved variant

featuring a 2- to 4-order of magnitude higher catalytic efficiency (kcat/Km) than the wild-type enzyme not only for

phenolic compounds but also for lignin model units and aromatic amines. For phenolics oxidation this variant

shows a pHopt = 8.4, 4.1 units up-shifted in relation to the wild-type enzyme. Noteworthy a 2-fold increase in the

protein production levels in relation to the wild-type was observed. Based on the model structure of PpDyP we

have rationalized the molecular basis for increased activity and production yields of the PpDyP enzyme. These

studies contributed to get a better insight on the structure-function relationships of the targeted enzymes with

impact in their applications in the realm of biotechnology.

Acknowledgements: This work was supported by the project grants EXP/BBB-BIO/1932/2013, PTDC/BBB-

EBB/0122/2014 and GREEN-IT "Bioresources 4 Sustainability" UID/Multi/04551/2013 from Fundação para a

Ciência e Tecnologia (FCT), Portugal.

References:

[1] L.O. Martins, P. Durao, V. Brissos, P.F. Lindley, Cell Mol Life Sci 72 (2015) 911-922.

[2] A. Santos, S. Mendes, V. Brissos, L.O. Martins, Appl Microbiol Biotechnol 98 (2014) 2053-2065.

[3] A.T. Fernandes, C.M. Soares, M.M. Pereira, R. Huber, G. Grass, L.O. Martins, FEBS J 274 (2007) 2683-2694.

[4] A.C. Sousa, M.C. Oliveira, L.O. Martins, M.P. Robalo, Green Chem. 16 (2014) 4127-4136.

[5] A.C. Sousa, M.F.M.M. Piedade, L.O. Martins, M.P. Robalo, Green Chem 17 (2015) 1429-1433.

[6] S. Mendes, M.P. Robalo, L.O. Martins, in: S.N. Singh (Ed.), Microbial Degradation of Synthetic Dyes in Waste

Waters, Springer, 2015, pp. 27-55.

[7] V. Brissos, M. Ferreira, G. Grass, L.O. Martins, ACS Catalysis 5 (2015) 4932-4941.

mailto:*[email protected]

FP1306 COST Action



24


New Added-value Chemicals, Polymers and Materials from renewable resources

A few examples @CICECO

Armando J. D. Silvestre* CICECO-Aveiro Institute of Materials and Department of Chemistry, University of Aveiro, Portugal

*[email protected]

The search for new chemicals, polymers and materials, from renewable resources has attracted an increasing

attention in recent years. The biorefinery concept, adressing the integrated and rational exploitation of biomass to

acheive this goal is therefore a transdisciplinary field of research that has grown enourmously in the last decades.

In the last decade our group has been intensively working in several domains of this global challenge, notably in

the extraction and upgrading of high-value components from biomass, in the production of biobased polymeric

materials, and functional (nano)materials, with an overarhching search for eco-friendly and sustainable

processes.

Examples of extraction and upgrading of biomass components include the extraction of triperpenic acids from

eucalyptus and oak cork, and the development of new methods for suberin extraction and valorization.

The production of poly(ethylene furandicarboxylate) and related polyesters- renewable analogs to the fossil

based therephthalic acid counterparts, is among the most promising activities in the polymer chemistry domains.

Finally we have been intensively working in the development of (nano)celulose based functional composites

with a wide panoply of natural and synthetic polymers, with applications spaning from biomedical domains to

films for transparent electronics.

A general overview of the resarch activities of the group will be put forward during this presentation.

mailto:*[email protected]

FP1306 COST Action



25


Energy production through syngas from ligno-cellulosic waste

Simona S. Merola1, Adrian Irimescu

1*, Fernando Colmenares

2 and Janka Dibdiakova

3

1CNR Istituto Motori, Via Marconi 4, 80125 Napoli, Italy 2Research Group TERMOMEC/Universidad Cooperativa de Colombia, Calle 50A No. 41-34, Medellín, Colombia

3Norwegian Institute of Bioeconomy Research, PO Box 115, NO-1431 Ås, Norway

*[email protected]

Introduction

Energy independence is a growing trend embraced by more and more stakeholders, given its advantages related

to security of supply. In this context, the use of several raw materials needs to be optimized in order to attain the

most beneficial economic and environmentally friendly situation. The ‘bottom-line’ is that the choice of

conversion technology is down to the requirements of the end-user1 and in the case of syngas obtained through

gasification of ligno-cellulosic biomass, spark ignition (SI) engines represent an easily adaptable2 and cost-

effective solution3. The main issues associated with the use of syngas in SI engines, are the wide range of

varying composition4,5

, power down-rating due to lower volumetric efficiency, as well as safety related

challenges, both with regard to high CO concentrations, as well as the presence of components that can damage

the engine6. This study presents the concept of optimizing syngas applications in the context of specific regional

characteristics of the raw material and requirements of end-users.

Methodology

The approach combines competencies of several research groups that cover the entire supply-use chain. On-site

analysis of the raw material represents the first step that provides data for syngas production investigations.

Gasification is the second step; the optimized combination of air-raw material ratio and thermodynamic

parameters are dictated by the minimum requirements of flammability and laminar flame speed. These two

parameters exert a crucial influence on engine operation (the third step in the chain), which determines efficiency

and overall environmental impact. Finally, information from all three categories provides the input for the

techno-economic, life-cycle analysis (LCA) and optimization; this last step influences the way gasification and

(indirectly) how the engine is controlled.

Fig. 1. Data flow and interconnections between workgroups.

Each category of the four investigative efforts is covered by a core group with specific expertize for that part,

joined by members of the other groups that focus on the other tasks. In this way, biomass treatment, analysis,

gasification, combustion in SI engines and techno-economic as well as environmental impact analysis are

covered, with corresponding flow of data and interconnections (Fig. 1).

Results, discussion and concluding remarks

Results obtained at each step constitute input data for the next category of investigations. Prospected results are a

database of raw materials from biomass and related properties of syngas under different thermodynamic

conditions, correlated with engine performance data, along with measured emissions. Considering the multi-

disciplinary nature of the undertaking, a methodology is proposed to cover all required skills through the

competencies of four research groups that form an international team to optimize the production-use chain.

References

1. T. Vogel, G. Oeljeklaus, T. Polklas, et al., MAN whitepaper (2016).

2. F.Y. Hagos, A.R.A. Aziz, S.A. Sulaiman, Energy, 90 2006 (2015).

3. C. Marculescu, V. Cenusa, F. Alexe, Waste Management, 47 133 (2016).

4. S.H. Han, D. Chang, W. Yang, Fuel, 181 277 (2016).

5. W. Zhang, X. Gou, W. Kong, et al., Fuel, 181 958 (2016).

6. L.F. de Diego, F. García-Labiano, P. Gayán, et al, Fuel Processing Technology, 152 116 (2016).

FP1306 COST Action



26


Lignin vinyl esters and their co-polymers with styrene, divinylbenzene and

triethoxyvinylsilane

Beata Podkościelna1, Oihana Gordobil

2, Anastasia V. Riazanova

3, Jalel Labidi

2, Olena Sevastyanova

3*

1 Maria Curie-Skłodowska University, Department of Polymer Chemistry, 20-031 Lublin, Poland; 2 University of the Basque Country, Chemical and Environmental Engineering Department, 20018 San Sebastián, Spain;

3 KTH-The Royal Institute of Technology, Wallenberg Wood Science Center, 100 44 Stockholm, Sweden.

*[email protected]

Introduction The increasing availability of various types of technical lignins as result of both the development of second

generation biofuel technologies and the emergence of new biorefineries that focus their production on bio-based

platform chemicals and commodities from lignocellulosic feedstock, boosted the interest in the

commercialization of various lignin-based materials and products. Lignins polyphenolic natural polymers, have

phenolic hydroxyl groups and aliphatic hydroxyl groups at the C-α and C-γ positions on the side chain, which

can be used for chemical modifications to increase the lignin reactivity. By means of the esterification of lignin

the new reactive groups can be introduced into its macromolecular structure to enable it to crosslink with various

polymeric systems. One such example is lignin derivatives with acrylate functionality or lignin vinyl esters.

Experimental Lignin samples were extracted from spruce (S) and eucalyptus (E) by Organosolv (OS, OE) and Kraft processes

(KS, KE) [1]. Methacryliation reaction was performed according to [2]. Porous microspheres were obtained by

the emulsion-suspension polymerization of lignin vinyl esters with divinylbenzene (DVB) and styrene (St) [3] or

with DVB and triethoxyvinylsilane (TEVS) [4]. Fourier transform infrared spectroscopy (FTIR) and quantitative 13

C NMR of lignins and lignin methacrylates were performed as described in [1]. Microspheres appearance and

morphology was determined using Hitachi S-4800 field-emission scanning electron microscope (SEM) with

accelerating voltage of 1 kV. The textural characteristics of composites were determined from low-temperature

(77.4 K) nitrogen adsorption–desorption isotherms recorded using a Micromeritics ASAP 2420 (V2.09 J)

adsorption analyser. The specific surface area (SBET) was calculated according to the standard BET method.


The attachment of methacrylic groups is expected to go through the hydroxyl groups in the lignin molecules. The

formation of new, characteristic for esters, bonds in all lignin samples was confirmed by FTIR method: a band at

1740 cm-1

, corresponding to the stretching vibrations of carbonyl groups (C=O) in an ester group and strong

band at 1120 cm-1

due to the C-O-stretching vibrations. The signals from the C=O group at 166 ppm, the double

bond signals at 128 and 135 ppm and the CH3 groups at 18 ppm, have been identified in the 13

C NMR spectra of

lignin samples, confirming the formation of lignin-methacrylate esters.

Table 1. Pore structure parameters of the

St-DVB-lignin copolymers

Copolymer SBET VTOT W

(m2 g-1) (cm3 g-1) (nm)

St-DVB

235

0.839

15.59

-OS 272 0.366 6.95

-OE 230 0.332 7.41

-KS 266 0.513 7.72 -KE 260 0.423 8.62

Figure 4. SEM images of ST-DVB microspheres containing lignin

methacrylates of OS, OE, KS and KE lignins. Scale bar is 50 µm.

Conclusions Polymeric mesoporous materials in the form of spherical microspheres were successfully prepared by

copolymerization of lignin vinyl derivatives with St-DVB or DVB-TEVS. Such materials can be suitable for the

sorption of phenolic pollutants from wastewater.

References

1. Gordobil, O., Moriana, R., Zhang, L., Labidi, J., Sevastyanova, O. (2016). Ind.Crops Prod., 83, 155-165.

2. Naveau, H.P. (1975). Cell. Chem. Technol., 9, 71-77.

3. Podkościelna, B., Sobiesiak, M., Zhao, Y., Gawdzik, B., O. Sevastyanova (2015). Holzforschung, 69(6), 769-776.

4. Podkościelna, B., Sevastyanova, O., Gawdzik, B. (2016). 16th POC, Crete, Greece, 13-16 June 2016.

FP1306 COST Action



27


Poster

Grafting of wheat straw fibers with PCL via ring-opening

polymerization for PLA reinforcement I. Kellersztein and A. Dotan *

Department of Polymers & Plastics Engineering, The Pernik Faculty of Engineering,

Shenkar College, Ramat Gan, Israel

Introduction

Fully biodegradable composites based on biodegradable polymers reinforced with natural fibers have emerged

recently as promising engineering composites. Agricultural waste can be a very economical source of natural

fibers, rich in cellulose, the most common polymer on earth and responsible for the mechanical support in plants.

Scouring and delignification treatments can help to increase significantly the amount of cellulose, improving the

mechanical and thermal stability of the fibers allowing thermal processing at higher temperatures [1]. The

present study aims the heterogeneous chemical surface modification of wheat straw fibers through ROP of PCL

to enhance the compatibility with PLA to improve mechanical properties.

Experimental

The grafting of PCL on scoured wheat straw fibers was made according to Lönnberg et al.[2]. After the grafting,

the modified wheat straw fibers were translocated to a Soxhlet extraction system for washing chemically un-

bonded PCL chains or adsorbed monomer and reagents remaining from the fibers using THF for 24 h.

Compounds containing 20wt% of treated and non-treated fibers in Revode190 (L130) PLA were produced in a

Thermo-Scientific HAAKE Rheomix OS at 175°C followed by hot pressing to produce plates for mechanical

tests. ATR, GPC, 1HNMR, TGA, Parallel Plate Rheometry and DSC characterization tests were also performed.


The molecular weight of the free polymer measured using GPC was 6521 g/mol, while the molecular weight of

the grafted PCL was calculated by 1H NMR was 7980 g/mol (according to the signals –CH2–OH end group at

3.67 and CH2–O repeating unit at 4.08). Mechanical tests results can be seen in Table 1.

Table 1. Characterization results of the different composites

Conclusions

Polycaprolactone was successfully grafted from scoured wheat straw fibers surface enabling a better

compatibility between the fibers and the PLA matrix. Thermal stability of natural fibers was improved by

scouring. PCL-grafted wheat straw fibers showed a Tonset of 302°C compared with 292°C for scoured fibers and

246°C for untreated fibers. The presence of PCL-grafted fibers led to a decrease in the degree of crystallinity of

the PLA because of the presence of entanglements and molecular interactions created between PCL-grafted

molecules with PLA chains. Those interactions also led to an increase in the friction between PCL and PLA

chains resulting in higher viscosity. Those molecular interactions enabled an increase in the toughness (20%

improvement of impact strength) and in the stiffness (24% improvement in flexural modulus and 15%

improvement in tensile modulus). Fully biodegradable composites based on PCL-grafted wheat straw fibers can

be an economically viable solution to reduce the CO2 footprint for applications where higher stiffness and impact

strength are needed [3].

References

1. I.Kellersztein, A. Dotan, Polym. Compos., (2015), DOI: 10.1002/pc.23392.

2. H. Lönnberg, Q. Zhou, H. Brumer III, T. T. Teeri, E. Malmström, and A. Hult, Biomacromolecules 2006, 7, 7.

3. I.Kellersztein, E. Amir, A. Dotan, Polym. Adv. Technol., (2015), DOI: 10.1002/pat.3736.

4.

FP1306 COST Action



28


List of participants

Argyropoulos, Dimitris Organic Chemistry of Wood Components Laboratory, Departments

of Forest Biomaterials and Chemistry,

North Carolina State University, Raleigh, 27695-8005, North

Carolina, USA

e-mail: [email protected]

Barsberg, Søren Uni. of Copenhagen,Rolighedsvej 23, DK-1958 Frederiksberg,

Denmark


Brissos, Vânia Instituto de Tecnologia Química e Biológica António Xavier,

Universidade Nova de Lisboa, Ava da República, 2780-901 Oeiras,

Portugal


Carvalho, Maria Graça CIEPQPF, Department of Chemical Engineering, University of

Coimbra, R. Sílvio Lima, Pólo II, 3030-790 Coimbra, Portugal


Christakopoulos, Paul Biochemical Process Engineering, Chemical Engineering,

Department of Civil, Environmental and Natural Resources



Crestini, Claudia Dipartimento di Scienze e Tecnologie Chimiche. Tor Vergata

University, Via della Ricarca Scientifica, 00133, Roma, Italy


Dotan, Ana Department of Polymers & Plastics Engineering, The Pernik

Faculty of Engineering,

Shenkar College, Ramat Gan, Israel


Erdocia, Xabier Chemical and Environmental Engineering Department, University

of the Basque Country, Plaza Europa 1, San Sebastián, Spain


Fernandes, Ana Raquel CIEPQPF, Department of Chemical Engineering, University of

Coimbra, R. Sílvio Lima, Pólo II, 3030-790 Coimbra, Portugal


Hodge, David Department of Chemical Engineering & Materials Science,

Michigan State University, East Lansing, Michigan, USA, and Department of Biosystems & Agricultural Engineering,

Michigan State University, East Lansing, Michigan, USA


Höfler Thomas Institute of Chemistry, Working Group “Chemistry and

Technology of Renewable Resources”, Graz University,

Heinrichstrasse 28, A-8010 Graz, Austria


Irimescu, Adrian CNR Istituto Motori, Via Marconi 4, 80125 Napoli, Italy


Kalliola, Anna VTT Technical Centre of Finland Ltd, Espoo, Finland



mailto:e-mail:%[email protected]


FP1306 COST Action



29


Karnaouri, Anthi Biochemical Process Engineering, Chemical Engineering,




Licini, Giulia Dipartimento di Scienze Chimiche, Università di Padova, via

Marzolo 1, 35131, Padova, Italy


Magdziarz, Agnieszka Institute of Physical Chemistry PAS, Kasprzaka 44/52, 01-224

Warsaw, Poland


Marques, Mara Instituto de Tecnologia Química e Biológica António Xavier,


Portugal


Martins, Lígia O. Instituto de Tecnologia Química e Biológica António Xavier,


Portugal


Masek, Ondrej UK Biochar Research Centre, University of Edinburgh, King’s

Buildings, Edinburgh, EH9 3FF, UK


Mendes, Sónia Instituto de Tecnologia Química e Biológica António Xavier,


Portugal


Merola, Simona CNR Istituto Motori, Via Marconi 4, 80125 Napoli, Italy


Milovanovic, Jelena Innovation Centre of the Faculty of Technology and Metallurgy,

University of Belgrade, Karnegijeva 4, 11120 Belgrade, Serbia


Prado Garcia, Raquel Department of Chemistry, Imperial College London, London SW7

2AZ, UK


Robalo, M. Paula Área Departamental de Engenharia Química, ISEL, Instituto

Politécnico de Lisboa, R. Conselheiro Emídio Navarro, 1, 1959-

007 Lisboa, Portugal and Centro de Química Estrutural,

Complexo I; IST-UL, Av. Rovisco Pais, 1049-001 Lisboa,

Portugal


Rova, Ulrika Biochemical Process Engineering, Chemical Engineering,



e-mail:[email protected]

Royo, Beatriz Instituto de Tecnologia Química e Biológica António Xavier,


Portugal


Santos, Diana Instituto de Tecnologia Química e Biológica António Xavier,






FP1306 COST Action



30


Portugal


Schwaiger, Nikolaus Graz University of Technology, Institute of Chemical Engineering

and Environmental Technology, Graz, Austria


Sevastyanova, Olena KTH-The Royal Institute of Technology, Wallenberg Wood

Science Center, 100 44 Stockholm, Sweden


Silva, Diogo Instituto de Tecnologia Química e Biológica António Xavier,


Portugal


Silvestre, Armando CICECO-Aveiro Institute of Materials and Department of

Chemistry, University of Aveiro, Portugal


Sousa, Ana Catarina Área Departamental de Engenharia Química, ISEL, Instituto

Politécnico de Lisboa, R. Conselheiro Emídio Navarro, 1, 1959-

007 Lisboa, Portugal and Centro de Química Estrutural,

Complexo I; IST-UL, Av. Rovisco Pais, 1049-001 Lisboa,

Portugal


Tamminen, Tarja VTT Technical Centre of Finland Ltd, Espoo, Finland


Triantafyllidis, Konstantinos Department of Chemistry, Aristotle University of Thessaloniki,

54124 Thessaloniki, Greece and Chemical Process and Energy

Resources Institute, CERTH, 57001 Thessaloniki, Greece





cost action fp1306 - photo-catalysis · fp1306 cost action joint wg1 & wg3 meeting lisbon,...

Documents