Study of Liquid-Liquid Equilibria of Toluene plus (Hexane, Heptane, or Cyclohexane) with 1-Ethyl-3-methylimidazolium Ethylsulfate at 308.15 K

The extraction of toluene from hydrocarbons (hexane, heptane, and cyclohexane) was analyzed by liquid extraction with 1-ethyl-3-methylimidazolium ethylsulfate [EMim][EtSO4] ionic liquid, as a solvent. The experimental liquid + liquid equilibrium (LLE) data were determined at T = 308.15 K and atmospheric pressure. Selectivity and distribution coefficient, derived from the tie-lines, were used to determine the ability of [EMim][EtSO4] as solvent for the separation of toluene from its mixtures with alkanes and cycloalkane. The degree of consistency of the experimental LLE data was ascertained using the Othmer-Tobias equation. The experimental data for LLE of the ternary systems were correlated with the nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) thermodynamic models.