TERNARY LIQUID-LIQUID EQUILIBRIA FOR {BENZENE + CYCLOHEXANE + DIFFERENT IONIC LIQUIDS } at T= 298.2 K and P=1 atm: EFFECT OF CATION AND ANION ON SEPARATION PERFORMANCE.

Ionic liquids (ILs) based on imidazolium and pyridinium cations and differenttypes of anions containing transition metals were investigated for extraction of benzene from cyclohexane. The Liquid-liquid equilibrium (LLE) data are presented for six ternary systems of (Cyclohexane + Benzene + an ionic Liquid) at 298.15 K and atmospheric pressure. The ILs used in these systems are [Bmim][FeCl4], [Bmim][AlCl4], [Bmim][CuCl2], [BuPy][FeCl4]), [BuPy][AlCl4], and [C6Py][FeCl4] were all prepared in the lab. The influence of cation and anion structure of ILs on the separation selectivity and capacity for aliphatic/aromatic mixtures was analyzed. The results indicate that most ILs investigated shows both higher extractive selectivity and capacity for the aromatic components for the systems studied herein, suggesting they can be used as promising extracts for the separation of aliphatic/aromatic mixtures. The LLE data were well correlated by the non-random two-liquid (NRTL) model of non-electrolyte solutions with overall ARD deviation being about 0.0001 interm of the mole fraction based activity.