Vapor–Liquid Equilibrium Experiment and Thermodynamic Model Correlation for Ethanol + Isopropyl Acetate with Ionic Liquid at 101.3 kPa

Due to the azeotrope between ethanol and isopropyl acetate, separating them and meeting the separation requirements is challenging. In this study, ethylene glycol (EG), dimethyl sulfoxide (DMSO), and 1-butyl-3-methyl-imidazole acetate ([BMIM]­[OAC]) were selected as entrainers, and the vapor–liquid equilibrium data of ethanol–isopropyl acetate, ethanol + isopropyl acetate + EG, ethanol + isopropyl acetate + DMSO, and ethanol-isopropyl acetate + [BMIM]­[OAC] were measured at atmospheric pressure. The thermodynamic NRTL model was able to fit these experimental results. It showed that the model could correctly describe the influence of these entrainers on this azeotropic system. According to the VLE data, three entrainers caused different effects on the relative volatility of ethanol–isopropyl acetate. The azeotropic point would be completely eliminated, while the mole fraction of [BMIM]­[OAC] added is 0.1, which performs better than EG and DMSO.