Separation of ethyl acetate and ethanol azeotropic system by acetate-based ionic liquid

Three ionic liquids (ILs)(1-ethyl-2,3-dimethylimidazolium acetate, [EMMIM][AC]; tributyl-methylammonium acetate, [N 4,4,4,1 ][AC]; and tetraethylammonium acetate, [N 2,2,2,2 ][AC]) were chosen. The vapor-liquid equilibrium (VLE) data of ternary mixtures (acetate + ethanol + IL) were gauged at 101.3KPa. NRTL equation was applied to correlate the data. From NRTL model, for [N 2,2,2,2 ][AC], [EMMIM][AC] and [N 4,4,4,1 ][AC], minimum mole fractions for completely eliminating azeotrope are 0.015, 0.020 and 0.022, respectively. From the average relative volatility and σ-profiles, it can be obtained that the separation ability order is [EMMIM][AC] > [N 2,2,2,2 ][AC] > [N 4,4,4,1 ][AC].