Dr Joe WoodSchool of Chemical EngineeringUniversity of Birmingham, UK

Amine Grafted Adsorbents for Efficient CO2 Capture

Midlands Energy Consortium International Showcase 5th October 2011

Overview Step-change Adsorbents For Carbon Capture

Nottingham, Birmingham, UCL, Liverpool. Sponsors EPSRC & E.ON

Post-combustion capture Hydrotalcite clays Amine grafting TGA studies of CO2 uptake

Next Generation of Activated Carbon Adsorbents for the Pre-Combustion Capture of CO2 UK-China CCS Call

Nottingham, Birmingham, UCL, Warwick, Tsinghua Universities, Chinese Inst. Coal Chemistry. UK Sponsor EPSRC

Pre-combustion capture CO2 breakthrough curves gProms modelling

Post-Combustion TechnologyAbsorption in to liquid amines Hydrotalcite solid adsorbent

Moving bed adsorption schematic

Step Change Adsorbents for Carbon Dioxide Capture Aim: To develop advanced adsorbents capable of

capturing > 3 mmol/g CO2

Adsorbents should also have desirable kinetics, stability and ability to be regenerated

Performance Parameter TargetOperating Temperature (C)

: adsorption 40 – 60 C: desorption 85 – 140 C

Cyclic capacity >3 mmol g-1

Rate of adsorption Order of secondsOperating pressure 1015 mbarPressure drop of capture plant Ideally < 2 psiCO2 product purity >95 %CO2 capture (of total emissions) >80 %

Proposed operating conditions for capture plant based on a temperature swing adsorption process (Drage et al, J. Materials Chem 2011).

Hydrotalcite Clays

•Hydroxycarbonate of Mg and Al•Brucite (Mg(OH)2) layers•Mg2+ ions substituted by other metals•(CO3)2- ions in the interlayer

Improved exfoliation method

TolueneUS

90oC,24h

Adding certain amount of water (eg. 0.3ml/g)

Brucite like layer

Mg2+ or Al3+

OH

Si

NH2

Dodecyl sulfate

Harlick, P. and Sayari, A. Ind. Eng. Chem. Res. 2007, 46, 446-458.

Different Types of Aminosilanes

(3-Aminopropyl)triethoxysilane (N1)

N-(2-Aminoethyl-3-aminopropyl) trimethoxysilane (N2)

N-3-(Trimethoxysilyl)propyl) diethylenetriamine (N3)

Si

O

OO

NH2

Si

O

OO

NH

NH2

Si

O

OO

NH

NHNH2

CO2 Adsorption by TGA

0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.086

88

90

92

94

96

98

100

0

20

40

60

80

100

120

MassTemp.

Time (min)

Mas

s (%

)

Tem

p (o

C)

Switch from N2 to CO2

CO2 adsorbed

Samples Prepared With Water –CO2 adsorption at 80 oC

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.450.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

N1N2N3

Water content (ml/g)

CO

2 up

take

(mm

ol/g

)

Next Generation of Activated Carbon Adsorbents for Pre-Combustion CO2 capture

Experimental Work

Experimental Work

Cycle 1 adjusted by 20% and cycle 2 by 10%

Zeolite X adsorbent

Equations Component Mass Balance

Adsorption rate equation

Approximated Langmuir equation

Assumptions Ideal gas law; Pressure drop by Darcy’s equation; Isothermal

operation; Bed in thermal equilibrium; No variation in radial direction

Modelling and Simulation

Modelling and Simulation

Decreasing Bed Length

Acknowledgements

EPSRC and E.ON Dr Jiawei Wang Dr Trevor Drage, Prof. Colin Snape and

STEPCAP project partners Simon Caldwell, Dr Bushra Al-Duri