Imidazolinium Ionic Liquid as Effective Separating Agent for Binary Azeotropic Systems

Abstract

One means of extractive distillation is salt rectification. Using an ionic liquid with an imidazolinium cation, binary azeotropic systems methyl acetate-methanol and ethyl acetate-ethanol are separated into components. 1,3-Dimethyl-2-phenylimidazolinium bromide is used as the imidazolinium salt. The effect organic salt has on the liquid-vapor equilibrium and the breaking of azeotropes in the systems is investigated in a modified Othmer still at 101.3 kPa via gas chromatographic analysis. It is found that concentrations of 1,3-dimethyl-2-phenylimidazolinium bromide (in mole fractions) of at least 0.2 and 0.25 are required for separating azeotropic systems methyl acetate-methanol and ethyl acetate-ethanol.