Solubility of CO₂ in the Ionic Liquids [bmim][CH₃SO₄] and [bmim][PF₆]

Abstract

A high-pressure view-cell technique based on the synthetic method was used to determine the solubility of carbon dioxide in the ionic liquid 1-n-butyl-3-methylimidazolium methyl sulfate ([bmim][CH 3 SO 4 ]). The temperature ranged from 293.2 K to 413.1 K, the pressure and the carbon dioxide molality reached up to ∼10 MPa and ∼3.3 mol of CO 2 ‚(kg of [bmim][CH 3 SO 4 ]) -1 , respectively. The (extended) Henry's law was successfully applied to correlate the solubility pressures. The final results for the Henry's constant (at zero pressure) of carbon dioxide in [bmim][CH 3 SO 4 ] (on the molality scale) are correlated within the estimated uncertainty (( 1.3 %) by ln(k H,CO 2 (0) /MPa) ) 7.2738 -1775/(T/K) -0.002033(T/K). Furthermore, some small corrections were applied to the experimental results for the solubility of carbon dioxide in the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF 6 ]) reported in previous work. The corrected values for the Henry's constant of carbon dioxide in [bmim][PF 6 ] only slightly and systematically deviate (by about -2 % at given temperature) from the values reported previously.

Thermodynamic modeling of CO2 solubility in ionic liquid with heterosegmented statistical associating fluid theory

“…tent and the calculated solubility agrees well with the experimental data. At 313 K, the experimental data are from four sources, and the solubility measured by Kumelan et al [9] ( ) and Aki et al [13] ( ) are higher than those by Shariati et al [1] (♦) and Liu et al [2] (+), especially at high pressures. The solubility calculated with the model is lower than the experimental solubility of Kumelan et al [9] ( ) and Aki et al [13] ( ) but higher than the experimental solubility of Shariati et al [1] (♦) and Liu et al [2] (+).…”

“…At 313 K, the experimental data are from four sources, and the solubility measured by Kumelan et al [9] ( ) and Aki et al [13] ( ) are higher than those by Shariati et al [1] (♦) and Liu et al [2] (+), especially at high pressures. The solubility calculated with the model is lower than the experimental solubility of Kumelan et al [9] ( ) and Aki et al [13] ( ) but higher than the experimental solubility of Shariati et al [1] (♦) and Liu et al [2] (+). At 333 K, the experimental solubility from Kumelan et al [9] ( ) is higher than those from Shariati et al [1], Liu et al [2], and Aki et al [13], and the calculated CO 2 solubility agrees well with the experimental data of Shariati et al [1], Liu et al [2] and Aki et al [13].…”

“…At 293 K, the experimental data are from Shariati et al [1] (♦) and Liu et al [2] (+). The experimental data are consis- [1]; +, experimental data [2]; , experimental data [9]; , experimental data [13]; -, calculated. tent and the calculated solubility agrees well with the experimental data.…”

“…The solubilities of gases in ILs have been measured by many researchers [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. However, due to the vast number of ILs that can be tailored the number of experimental investigations needed is less than adequate.…”

Transport Properties of Binary Mixtures of Carbon Dioxide and 1-Butyl-3-methylimidazolium Hexafluorophosphate Studied by Transient Grating Spectroscopy

“…1 Due to this unique character of the phase behavior, the system has potential applications for extraction or purification as a green solvent. The solubility of CO2 in various RTILs has been extensively studied [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] and the structure of the binary mixture has been studied experimentally and theoretically. [18][19][20][21][22] On the other hand, reports on transport properties of these systems such as viscosity and diffusion are still limited in spite of their importance in designing chemical processes.…”