Solubility of CO2 in Acetone, 1-Butyl-3-methylimidazolium Tetrafluoroborate, and Their Mixtures

The phase behavior of binary and ternary mixtures consisting of carbon dioxide (CO2) (1), acetone (2), and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM](+)[BF4](-)) (3) was studied experimentally. A high-pressure view-cell technique was used to measure the solubility data in the solvent mixtures of acetone and [BMIM](+)[BF4](-) at various mole contents at temperatures of (298.2, 313.2 and 323.2) K and pressures up to 6.0 MPa. The experimental solubility data were correlated using the Henry's law and Peng-Robinson equation of state (PR EOS), and the magnitude of Henry's constants is in the order of H-X3=0.0 < H-X3=0.060 < H-X3=0.204 < H-X3=0.507 < H-X3=1.0 at a given temperature. Moreover, at a fixed mole ratio of organic solvent to ionic liquid (IL), the solubility of CO2 in the mixture of acetone and [BMIM](+)[BF4](-) is the highest when compared with other previously reported organic solvent + IL separating agents. The mixtures of acetone and [BMIM](+)[BF4](-) may be used as a potential solvent for industrial application for capturing CO2 efficiently and effectively.