2
0
2016
zho
sha
0
journal
Original
Zhou, L.[Lingyun]
Shang, X.[Xiaomin]
Fan, J.[Jing]
Wang, J.[Jianji]
J. Chem. Thermodyn.
2016
2020-09-29
Solubility and selectivity of CO2 in ether-functionalized imidazolium ionic liquids
Ionic liquids are widely recognized new materials in carbon dioxide capture and separation technology. In this work, we synthesized and characterized two kinds of ether-functionalized imidazolium ionic liquids, 1-methoxyethyl-3-methylimidazolium hexafluoroborate ([EOMmim][PF6]) and 1-methoxyethyl-3- methylimidazolium bis(trifluoro-methylsulfony)imide ([EOMmim][Tf2N]). Solubility values of CO2 in these ionic liquids were determined by isometric weight method at the temperatures from 298.15 K to 343.15 K and the pressure up to 5.185 MPa. Furthermore, solubilities of other flue gases, N2 and O2, in these two ionic liquids were also measured at 303.15 K. It was shown that little influence had been exerted on CO2 solubility by the introduction of ether groups on the cation, but it decreased N2 and O2 solubility, resulting in the remarkable increase of CO2/N2 and CO2/O2 selectivity. In addition, the solubility data were well correlated by Pitzer model, and the standard state solution Gibbs energy, solution enthalpy and solution entropy of CO2 in the two ionic liquids were reported. Regeneration characteristics of the investigated ionic liquids was also studied by vacuum desorption and atmospheric desorption, respectively.
Ether-functionalized ionic liquid
CO2
Solubility
Selectivity
Regeneration
10.1016/j.jct.2016.08.028
103
292-298
1
InChI=1S/C7H13N2O.F6P/c1-8-3-4-9(7-8)5-6-10-2;1-7(2,3,4,5)6/h3-4,7H,5-6H2,1-2H3;/q+1;-1
KOUMVOPZBXUAFT-UHFFFAOYSA-N
1-(2-methoxyethyl)-3-methyl-imidazolium hexafluorophosphate
C7H13F6N2OP
1
Synthesized by the authors
1
Dried by vacuum heating
Solvent extraction
Dried by vacuum heating
Solvent extraction
2
0.06
1
Karl Fischer titration
3
99.6
3
NMR (proton)
2
InChI=1S/C7H13N2O.C2F6NO4S2/c1-8-3-4-9(7-8)5-6-10-2;3-1(4,5)14(10,11)9-15(12,13)2(6,7)8/h3-4,7H,5-6H2,1-2H3;/q+1;-1
QTWXKUATXFJTAM-UHFFFAOYSA-N
1-(2-methoxyethyl)-3-methyl-1H-imidazolium bis((trifluoromethyl)sulfonyl)amide
3-(2-methoxyethyl)-1-methylimidazolium 1,1,1-trifluoro-N-[(trifluoromethyl)sulfonyl]methanesulfonamide
C9H13F6N3O5S2
1
Synthesized by the authors
1
Dried by vacuum heating
Solvent extraction
Dried by vacuum heating
Solvent extraction
2
0.09
1
Karl Fischer titration
3
99.2
3
NMR (proton)
3
InChI=1S/CO2/c2-1-3
CURLTUGMZLYLDI-UHFFFAOYSA-N
carbon dioxide
CO2
1
Commercial source
1
99.995
5
Stated by supplier
4
InChI=1S/N2/c1-2
IJGRMHOSHXDMSA-UHFFFAOYSA-N
nitrogen
N2
1
Commercial source
1
99.99
4
Stated by supplier
5
InChI=1S/O2/c1-2
MYMOFIZGZYHOMD-UHFFFAOYSA-N
oxygen
O2
1
Commercial source
1
99.95
4
Stated by supplier
1
3
1
1
1
Principal objective of the work
AB
TRC
2/2/2017
1
Molality, mol/kg
volumetric method
3
Liquid
Direct value, X
1
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
Gas
1
Pressure, kPa
Liquid
2
Temperature, K
Liquid
1
1062
4
2
298.15
5
1
0.6592
4
1
0.0264
1
2018
4
2
298.15
5
1
1.2566
5
1
0.0503
1
2788
4
2
298.15
5
1
1.7575
5
1
0.0704
1
3478
4
2
298.15
5
1
2.1722
5
1
0.0869
1
3935
4
2
298.15
5
1
2.4455
5
1
0.0979
1
4275
4
2
298.15
5
1
2.6568
5
1
0.1063
1
4656
4
2
298.15
5
1
2.8606
5
1
0.1145
1
1147
4
2
303.15
5
1
0.639
3
1
0.026
1
2144
4
2
303.15
5
1
1.1672
5
1
0.0467
1
2995
4
2
303.15
5
1
1.6328
5
1
0.0654
1
3613
4
2
303.15
5
1
1.9775
5
1
0.0792
1
4105
4
2
303.15
5
1
2.2418
5
1
0.0897
1
4533
4
2
303.15
5
1
2.4586
5
1
0.0984
1
4930
3
2
303.15
5
1
2.6668
5
1
0.1067
1
1212
4
2
313.15
5
1
0.5795
4
1
0.0232
1
2227
4
2
313.15
5
1
1.0361
5
1
0.0415
1
3100
2
2
313.15
5
1
1.395
5
1
0.0558
1
3719
4
2
313.15
5
1
1.6556
5
1
0.0663
1
4211
4
2
313.15
5
1
1.9002
5
1
0.0761
1
4650
3
2
313.15
5
1
2.088
4
1
0.084
1
5057
4
2
313.15
5
1
2.2613
5
1
0.0905
1
1239
4
2
323.15
5
1
0.49276
5
1
0.01974
1
2130
3
2
323.15
5
1
0.8264
4
1
0.0331
1
2871
4
2
323.15
5
1
1.1243
5
1
0.045
1
3552
4
2
323.15
5
1
1.3788
5
1
0.0552
1
4084
4
2
323.15
5
1
1.5745
5
1
0.063
1
4586
4
2
323.15
5
1
1.7526
5
1
0.0701
1
4961
4
2
323.15
5
1
1.845
5
1
0.0738
1
1276
4
2
333.15
5
1
0.442
4
1
0.0177
1
2266
4
2
333.15
5
1
0.7715
4
1
0.0309
1
3151
4
2
333.15
5
1
1.053
5
1
0.0421
1
3807
4
2
333.15
5
1
1.2541
5
1
0.0502
1
4306
4
2
333.15
5
1
1.4029
5
1
0.0562
1
4719
4
2
333.15
5
1
1.539
5
1
0.0616
1
5115
4
2
333.15
5
1
1.6867
5
1
0.0675
1
1276
4
2
343.15
5
1
0.3876
4
1
0.0155
1
2261
4
2
343.15
5
1
0.6736
4
1
0.027
1
3164
4
2
343.15
5
1
0.9296
4
1
0.0372
1
3843
4
2
343.15
5
1
1.1062
5
1
0.0443
1
4363
4
2
343.15
5
1
1.2517
5
1
0.0501
1
4790
3
2
343.15
5
1
1.3637
5
1
0.0546
1
5185
4
2
343.15
5
1
1.4901
5
1
0.0596
2
3
1
2
1
Principal objective of the work
AB
TRC
2/2/2017
1
Molality, mol/kg
volumetric method
3
Liquid
Direct value, X
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
Gas
1
Temperature, K
Liquid
2
Pressure, kPa
Liquid
1
298.15
5
2
1052
4
1
0.8496
4
1
0.034
1
298.15
5
2
1973
4
1
1.5976
5
1
0.0641
1
298.15
5
2
2690
3
1
2.1984
5
1
0.0881
1
298.15
5
2
3233
4
1
2.6441
5
1
0.106
1
298.15
5
2
3666
4
1
2.9851
5
1
0.1197
1
298.15
5
2
4028
4
1
3.3066
5
1
0.1325
1
298.15
5
2
4282
4
1
3.5526
5
1
0.1424
1
303.15
5
2
1059
4
1
0.7735
4
1
0.031
1
303.15
5
2
1935
4
1
1.4009
5
1
0.0562
1
303.15
5
2
2609
4
1
1.8727
5
1
0.0751
1
303.15
5
2
3141
4
1
2.2664
5
1
0.0909
1
303.15
5
2
3562
4
1
2.5879
5
1
0.1037
1
303.15
5
2
3916
4
1
2.8697
5
1
0.115
1
303.15
5
2
4189
4
1
3.0993
5
1
0.1242
1
313.15
5
2
1295
4
1
0.7777
4
1
0.0311
1
313.15
5
2
2189
4
1
1.3096
5
1
0.0525
1
313.15
5
2
2874
4
1
1.7258
5
1
0.0692
1
313.15
5
2
3411
4
1
2.0126
5
1
0.0807
1
313.15
5
2
3826
4
1
2.2706
5
1
0.091
1
313.15
5
2
4158
4
1
2.492
5
1
0.0999
1
313.15
5
2
4395
4
1
2.6571
5
1
0.1065
1
323.15
5
2
1429
4
1
0.7351
4
1
0.0294
1
323.15
5
2
2263
4
1
1.143
5
1
0.0458
1
323.15
5
2
2946
4
1
1.4938
5
1
0.0599
1
323.15
5
2
3461
4
1
1.7302
5
1
0.0694
1
323.15
5
2
3864
4
1
1.9437
5
1
0.0779
1
323.15
5
2
4228
4
1
2.1284
5
1
0.0853
1
323.15
5
2
4517
4
1
2.3092
5
1
0.0926
1
333.15
5
2
1432
4
1
0.6383
4
1
0.0256
1
333.15
5
2
2334
4
1
1.0254
5
1
0.0411
1
333.15
5
2
3012
4
1
1.3198
5
1
0.0529
1
333.15
5
2
3545
4
1
1.5362
5
1
0.0616
1
333.15
5
2
3911
4
1
1.6802
5
1
0.0674
1
333.15
5
2
4254
4
1
1.8491
5
1
0.0741
1
333.15
5
2
4591
4
1
2.0259
5
1
0.0812
1
343.15
5
2
1406
4
1
0.5611
4
1
0.0225
1
343.15
5
2
2292
4
1
0.8996
4
1
0.036
1
343.15
5
2
2995
4
1
1.169
5
1
0.0469
1
343.15
5
2
3558
4
1
1.3809
5
1
0.0554
1
343.15
5
2
3978
4
1
1.5451
5
1
0.0619
1
343.15
5
2
4301
4
1
1.6562
5
1
0.0664
1
343.15
5
2
4612
4
1
1.7893
5
1
0.0717
3
4
1
1
1
Principal objective of the work
AB
TRC
2/2/2017
1
Molality, mol/kg
volumetric method
4
Liquid
Direct value, X
1
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
Gas
1
Temperature, K
Liquid
303.15
5
1
Pressure, kPa
Liquid
1
1027
4
1
0.0601
3
1
0.0024
1
2070
3
1
0.0885
3
1
0.0035
1
2689
4
1
0.1037
4
1
0.0041
1
3264
4
1
0.1154
4
1
0.0046
1
3885
4
1
0.1293
4
1
0.0052
1
4441
4
1
0.1419
4
1
0.0057
1
5067
4
1
0.1544
4
1
0.0062
4
5
1
1
1
Principal objective of the work
AB
TRC
2/2/2017
1
Molality, mol/kg
volumetric method
5
Liquid
Direct value, X
1
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
Gas
1
Temperature, K
Liquid
303.15
5
1
Pressure, kPa
Liquid
1
1002
4
1
0.0475
3
1
0.0019
1
2125
4
1
0.0763
3
1
0.0031
1
2817
4
1
0.0901
3
1
0.0036
1
3585
4
1
0.1058
4
1
0.0042
1
4140
3
1
0.1169
4
1
0.0047
1
4834
4
1
0.1305
4
1
0.0052
1
5578
4
1
0.1466
4
1
0.0059
5
4
1
2
1
Principal objective of the work
AB
TRC
2/2/2017
1
Molality, mol/kg
volumetric method
4
Liquid
Direct value, X
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
Gas
1
Temperature, K
Liquid
303.15
5
1
Pressure, kPa
Liquid
1
1385
4
1
0.0734
3
1
0.0029
1
2492
4
1
0.0984
3
1
0.0039
1
3211
4
1
0.1203
4
1
0.0048
1
3853
4
1
0.1415
4
1
0.0057
1
4402
4
1
0.1548
4
1
0.0062
1
4907
4
1
0.1738
4
1
0.007
1
5596
4
1
0.1902
4
1
0.0076
6
5
1
2
1
Principal objective of the work
AB
TRC
2/2/2017
1
Molality, mol/kg
volumetric method
5
Liquid
Direct value, X
2
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
Gas
1
Temperature, K
Liquid
303.15
5
1
Pressure, kPa
Liquid
1
1212
4
1
0.0629
3
1
0.0025
1
2407
4
1
0.0935
3
1
0.0037
1
3164
4
1
0.1133
4
1
0.0045
1
3820
3
1
0.131
5
1
0.00524
1
4409
4
1
0.1486
4
1
0.0059
1
4815
4
1
0.1568
4
1
0.0063
1
5546
4
1
0.1728
4
1
0.0069