26 April 2015 1

On the Performance of Porous Covalent

Organic Polymers for CO2 Capture Process

at Elevated Pressures

Water and Energy Workshop

Organized by Texas A&M University at Qatar

RUH ULLAH

Research Fellow

Department of Chemical Engineering, Qatar University

February 17, 2015

Doha, Qatar

26 April 2015 2

Outline

Global concern of carbon dioxide capture and storage

Technologies in use

Materials selection for CO2 capture

Synthesis and characterization of covalent organic

polymers (COPs)

Material performance for gases capture at various

temperatures and pressures

Adsorption kinetics

Conclusion

26 April 2015 3

0

2

4

6

8

10

12

14

16

20

35

20

35

20

10

Global CO2 Emission

13.1

15.3

5.3

Power Generation & CO2 Emission

26 April 2015 5

Current Technologies

Post combustion

Fossil fuel or biomass is burnt and CO2 is separated from the

exhaust gases containing other gases

Pre-combustion

Fossil fuel or biomass is converted to a mixture of H2 and CO2,

where CO2 is separated and H2 is used as fuel

Oxy-fuel combustion

Oxygen is separated from air and fossil fuels burnt in an

atmosphere of oxygen producing water and CO2

26 April 2015 6

Solvents

Monoethanolamine (MEA), mostly used, but, costly

Ionic liquid are very expensive and toxic

Deep eutectic solvents; new technology???

Membranes

Polybenzimidazole, need to be selective and tough

Adsorbents

Activated Carbon and MOF, need highly porous structure

with high surface area

Organic Polymer ???

Capturing Technologies

26 April 2015 7

Material Selection (MoF)

• Metal Organic Frame Work

• Surface area: 4530 m2/g

• Pore volume: 3.59 cm3/g

• Maximum CO2 uptake at 50 bars and 298k

• 54.5 mmol/g

• Oxidation and cost of materials are big

issues

26 April 2015 8

Material Selection (Zeolite)

• Surface area: 2400 m2/g

• Pore volume: 0.167 cm3/g

• Maximum uptake at 1 bar and 273K: 8.6

mmol/g

• Maximum uptake at 20 bars 0.0051 mmol/g

• Hydrophilic in nature

• Needs high regeneration temperature (300 oC)

26 April 2015 9

Material Selection (Activated Carbon)

Pore size Micropoers Mesopores Macropores

Diameter < 20 nm 20-50nm >50 nm

Pore

volume

(cm3/g)

0.15—0.5 0.020.1 0.5

Surface

area(m2/g)

100-1000 10-100 0.5-2

• Surface area: 2900 m2/g

• CO2uptake at 50 bar: 47 mmol/g

• Limitation at high pressure

26 April 2015 10

Atilhan Group

10

COFs

MOFs

DLH

Prussian Blue

MCO3Urea

Ionic Liquids

Amines

Zeolites

26 April 2015 11

• Continuous innovation in control of:

– Pore structure/ connectivity

– Dimensionality and symmetry

– Adsorbate site interactions

• Porous solid adsorbent material can be designed to be highly size- and shape-selective.

Engineering Polymers

26 April 2015 12

Ester (O=C-O) COPs

Core / Linker OHHO

Hydroquinone HO

HO

OH

Phloroglucinol

OH

OH

Bisphenol A

COCl

COClClOC Benzene

tricarbonyl trichloride

COP-35

SABET: 5.4 m

2/g

SALang.: 7.5 m

2/g

COP-36

SABET: 11.1 m

2/g

SALang.: 15.4 m

2/g

COP-37 SABET: 54.2 m

2/g

SALang.: 75 m2/g

Amide (O=C-N) COPs

NH2

H2N

4-aminobenzylamine

NH2H2N

p-phenylenediamine

NH2H2N m-phenylenediamine

COP-32

SABET: 46 m

2/g

SALang.: 63.8 m

2/g

COP-33

SABET: 53.2 m

2/g

SALang.: 73.4 m

2/g

COP-34

SABET: 33.4 m

2/g

SALang.: 46.2 m

2/g

Polymer Synthesis

26 April 2015 13

Physical Properties of COPs

Sample code

Structure Surface area, m2/g

Pore volume (cm3/g)

Tapped bulk density, cm3/g

COP-32 O

O

O

HN

HN

BET = 46 Langmuir = 63.8

0.1389 0.19

COP-33 O

O

O

HN

NH

BET = 53.2 Langmuir = 73.4

0.2 0.156

COP-34 O

O

O

HN

HN

BET = 33.4 Langmuir = 46.2

0.095 0.253

COP-35 O

O

O

O

O

BET = 5.4 Langmuir = 7.5

0.011 0.125

COP-36 O

O

O

O

O

BET = 11.1 Langmuir = 15.4

0.031 0.22

COP-37 O

O

O

O O

BET = 54.2 Langmuir = 75

0.19 0.2

26 April 2015 14

100 200 300 400 500 600 700 800

30

40

50

60

70

80

90

100

We

igh

t l

oss /

% w

t.

Temperature / o

C

COP-32

COP-33

COP-34

COP-35

COP-36

COP-37

4000 3500 3000 2500 2000 1500 1000 500

Wavelength / cm-1

COP-32

COP-33

COP-34

Tra

nsm

ittan

ce /

%

COP-33

COP-36

COP-37

COPs Characterization

26 April 2015 15

CO2 Solubility Measurements

• We used Rubotherm® sate-of-the-art gas

sorption apparatus.

• Two isotherms are used: 25 °C and 50 °C

• Three pressures ranges were used i.e. 1 bar, 10

bars and 200 bars.

• Buoyancy correction has been taken care of.

26 April 2015 16

Operating Principle

Schematics of magnetic suspension

sorption apparatus operating principle.

(A) sample loaded to measuring basket

in high pressure cell; (B) Measurement

point 1 (MP1) – magnetic coupling is

on and mass of the sample is measured;

(C) Measurement point 2 (MP2) – in–

situ density of the adsorbed gas is

measured.

26 April 2015 17

CO2 Up take

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7CO

2 Adsorption at 298 K and 1 bar

COP-33-A

COP-35-A

COP-36-A

COP-37-A

COP-34-A

COP-32-A

Up

tak

e (m

mol

/g)

Pressure (bars)

26 April 2015 18

CO2 Up take

26 April 2015 19

0 1 2 3 4 5 6 7 8 9 10

0.0

0.5

1.0

1.5

Up

ta

ke

(m

mo

l/g

)

Pressure

CO2

(298 K)

CO2

(323 K)

N2

(298 K)

N2

(298 K)

CH4

(298 K)

CH4

(298 K)

COP-33

CO2 Up take of COP-33

26 April 2015 20

0 1 2 3 4 5 6 7 8 9 10

0.0

0.1

0.2

0.3

0.4

Methane (298 K)

Up

ta

ke

(m

mo

l/g

)

Pressure (Bars)

COP-32

COP-33

COP-37

COP-35

COP-36

COP-34

CH4 Up take of COP

26 April 2015 21

Temp/Materi

al 298K 323K 298K 323K 298K 323KCOP32 1.109213 0.804201 0.223124 0.081515 0.080872 0.037786

COP33 1.440349 0.981784 0.410248 0.289082 0.61099 0.259958

COP34 1.116972 0.778442 0.41324 0.188905 0.177384 0.05648

COP35 0.819419 0.554221 0.18187 0.130621 0.08249 0.059161

COP36 0.557371 0.3717 0.0659 0.018713 0 0

COP37 1.140691 0.723342 0.190126 0.107208 0.212632 0

Maximum adsorption of N2, CO2 and CH4 by COP

CO2 (mmol/g ) Methane (mmol/g) N2 (mmol/g)

CH4, N2 and CO2 Up take

26 April 2015 22

0 50 100 150 200

0

10

20

30

40

50

60

70

COP-33

Up

tak

e (m

mol/

g)

Pressure (bars)

CO2

H2

N2

CH4

CO2 Up take of COP-33

26 April 2015 23

2 4 6 8 10

0.003

0.004

0.005

0.006

0.007

0.008

0.009

0.010

0.011

0.012K

(se

c-1)

Pressure (bars)

CO2 (298 k)

CO2 (323 k)

Mass transfer co efficient (k)

26 April 2015 24

2 4 6 8 10

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

K (

sec

-1)

CO2 (298 K)

Pressure (Bars)

COP-33

COP-34

COP-37

COP-36

COP-35

COP-32

Mass transfer co efficient (k)

26 April 2015 25

COP-33 COP-37 COP-34 COP-32 COP-35 COP-36

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Up

ta

ke

(m

mo

l/g

)

Materials

CO2 (298 K)

CO2 (323 K)

CH4 (298 K)

CH4 (323 K)

N2 (298 K)

N2 (323 K)

Over all performance

26 April 2015 26

Group…

26

26 April 2015 27

Funding

• QNRF

– NPRP 5-499-1-088

– UREP 15-131-2-044

• Spanish National Secretariat for Research and

Development, Ministry of Economy.