Liquid−liquid equilibrium (LLE) of a ternary mixture of water, 2,3-butanediol, and 4-methyl-2-pentanol has been measured at three different temperatures (298.2, 308.2, and 318.2 K) under atmospheric pressure. The experimentally measured solubility and tieline data for the two-phase system were used to construct a ternary phase diagram at each temperature. With the experimental data, the distribution coefficients and separation factors were also calculated and Othmer− Tobias and Hand plots were used to verify the consistency of the measured data. The universal quasichemical (UNIQUAC) and nonrandom-two liquid (NRTL) models were used for the LLE, and the rootmean-square deviation values between the calculated and experimental data were less than 1.21% by the UNIQUAC model and less than 1.96% by the NRTL model, indicating that both model calculations provide excellent agreement with the experimentally measured LLE data in the present study.

The solubility of carbon dioxide (CO 2 ) in three different ionic liquids (ILs):and 1-benzyl-3-methylimidazolium 1,1,2,2-tetrafluoroethanesulfonate ([BNMIM][TFES]) were measured. Measurements were done at temperatures ranging from 303.2 to 373.2 K (323.2 to 373.2 K for [BNMIM][TFES]) at pressures from 0.80 to 36.80 MPa. Measured data show that pressure, temperature, and characteristics of cation of ILs ([EMIM], [BMIM], and [BNMIM]) affect its CO 2 solubility. We determined the CO 2 solubility of fixed CO 2 mole fractions for three ionic liquids. Among the three ILs, CO 2 solubility intensity was ranked. The Peng− Robinson equation of state, the conventional van der Waals one-fluid mixing rule, and the modified Lydersen−Joback−Reid method were used to correlate the experimental data. The average absolute deviations of pressure were 0.0164 for CO 2 + [EMIM][TFES], 0.0361 for CO 2 + [BMIM][TFES], and 0.0251 for CO 2 + [BNMIM][TFES] systems.