Measurement and Correlation of CO2 Solubility in 1-Ethyl-3-methylimidazolium ([EMIM]) Cation-Based Ionic Liquids: [EMIM][Ac], [EMIM][Cl], and [EMIM][MeSO4]

The solubility of carbon dioxide (CO2) was investigated using three different 1-ethyl-3-methylimidazolium ([EMIM]) cation-based ionic liquids: 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]), 1-ethyl-3-methylimidazolium chloride ([EMIM][Cl]), and 1-ethyl-3-methylimidazolium methyl sulfate ([EMIM][MeSO4]). The CO2 solubility data for the three ionic liquids were produced by measuring the bubble-point and cloud-point pressures of the CO2 + ionic liquid mixtures. The temperature range was from 303.15 to 403.15 K, and the pressure range was from 0.45 to 48.6 MPa. The experimental data provided results showing that the solubility of CO2 in ionic liquids increased with pressure, decreased with temperature, and was also affected by the different anions used in the experiment. The solubility is determined by CO2 mole fraction in ionic liquids, and the order of magnitude of the CO2 solubility was found to be [EMIM][Ac] > [EMIM][MeSO4] > [EMIM][Cl]. For the correlation and calculation of the experimental data, we ...