Vapor–Liquid Equilibrium for Methyl Acetate + Ethanol + 1,3-Dimethy-limidazoledimethyl Phosphate

Because of the azeotropic phenomenon, separating methyl acetate and ethanol is not an easy task. Extractive distillation is a suitable separation technique, and ionic liquid 1,3-dimethy-limidazoledimethyl phosphate ([MMIM][DMP]) and organic solvent dimethyl sulfoxide (DMSO) are chosen as the entrainers in this work. Vapor–liquid phase equilibrium experiments were conducted at 101.3 kPa. The nonrandom two-liquid model was selected to fit the experimental data, and it was in accordance with the calculated data. It can be concluded that [MMIM][DMP] and DMSO can eliminate the azeotropic phenomenon of methyl acetate + ethanol completely. The effect of [MMIM][DMP] for separation is much better than that of DMSO which proves tremendous potential for the application of ionic liquids.