1. King Saud University, Saudi Arabia
CO2 Capture Using Deep
Eutectic Solvents
Prof.  Emadadeen  M.  Ali
King Saud University, Saudi Arabia

2. Global Worming Global Warming Fossil fuels (coal, oil, natural gas)
Carbon Dioxide (CO2)
Fossil fuels (coal, oil, natural gas)

3. Sources of CO2 emissions

4. World-wide statistical data of CO2

5. CO2 separation process
Separation using Sorbent/Solvent

6. Solvent Characteristics
Preparation and material Cost
Environmental impact
Capacity

7. MEA Advantage & Disadvantages
MEA: Monoethanolamin is the most common material used in industry to absorb CO2
Advantages
Inexpensive material (1ton of MEA cost $1100)
Disadvantages
Low carbon dioxide loading capacity
Equipment corrosion
High-energy penalty during absorbent regeneration

8. Ionic Liquids
A new class of compounds that have emerged in the last twenty years with several applications in chemical and physical separation.
ILs are environmentally-friendly alternatives to organic solvent for liquid/liquid extraction, and separation.
ILs face a challenge in large-scale industrial applications, due to complicated synthetic processes and the expensive raw material chemicals

9. Deep Eutectic Solvents
deep eutectic solvents (DESs) have been recognized as a cost effective alternative to ILs
DESs possess several advantages over traditional ILs., they can be prepared easily in high purity at low cost.
In addition, they are non-toxic, have no reactivity with water and most importantly being biodegradable

10. Objectives Prepare different types of DES
Test the solubility of CO2 in these DES
Model the CO2 solubility using
Peng-Robinson EoS

11. EC 400 Variable volume high pressure equilibrium cell (SEPAREX, France).

12. Experiment Protocol
The visual cell is cleaned, evacuated using vacuum pump, and kept at fixed temperature using a circulating water bath.
A pre-determined amount of DES is introduced to the cell using the HPLC pump. CO2 is then introduced to the cell at a certain pressure.
The mixture is stirred using the magnetic bar until equilibrium is achieved.
The change in the volume of cell is recorded. The mass of dissolved CO2 is calculated using Benedict-Webb-Robin equation of state

13. Solubility Modeling
Peng Robinson Equation of State
Subject to:

14. Solubility and physical properties of DES at T=25 oC, P=125 psi
Code
Components
Ratio x
Tc, K
Pc, bar w
D01 Bc
Glycerol 1 12
0.0511
749.0
34.1
1.4
D02 Bb
Ethylene Glycol
0.0503
632.3
46.5
1.0
D03 Mb
Ethanol Amine 6
0.1441
654.1
44.0
0.7
D04 7
0.1254
646.0
45.1
D05 8
0.1189
639.8
46.1
D06 CC
0.1096
594.1
48.9
D07
Di Ethanol Amine
0.0925
693.4
29.7
1.1
D08
TAB
0.1168
613.8
39.2
D09
0.1036
717.7
25.5
D10
Tri Ethanol Amine 3
0.0830
795.7
19.3
BC: Benzyltryphenilphosphonium chloride, BB:n-Butyltriphenylphosphonium bromide,
MB: Methyltriphenylphosphonium bromide, TAB: Tetra Butyl Ammonium Bromide

15. Solubility and physical properties of CC-salt /des at T=25 oC
Code
Components
Ratio
Pressure (bar) x
Tc, K
Pc, bar w I2 CC TG 1 4
1.38
0.0003
718.9
27.4
1.04
5.12
0.0021
8.61
0.0028
13.80
0.0101
CC: Choline Chloride, TG: Triethylene Glycol

16. Comparison of CO2 solubility in DESs, ♦: experimental; ▲: model; □: corrected model

17. : CO2 solubility in CC-based DEs with pressure, ♦: experimental; ▲: model with fixed k; □: model with variable k

18. Conclusions
The solubility of CO2 in ethylene glycol and glycerol based DESs is much smaller than that in MEA aqueous solution
The solubility depended on the type of salt used and on the salt:HBD molar ratio.
The modeling results indicated the necessity to adjust the interaction parameter in order to improve the ability of the PR EoS to predict the CO2 solubility

19. Thank you