Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

Ionic liquid (IL) was selected as extractive distillation entrainer to separate the binary mixture of methanol and methyl propionate with the lowest azotropic temperature. Experimental determination of isobaric vapor-liquid equilibrium for the system of methanol + methyl propionate + 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][NTf2]) was made at atmospheric pressure with an all-glass dynamic recirculating still. The results show that the addition of [BMIM][NTf2] can produce an obvious salting-out effect and well enhances the relative volatility of methanol to methyl propionate, and the azeotropy of the investigated binary system is ultimately eliminated by increasing the concentration of IL to a certain value in liquid phase. Additionally, the experimental data were well fitted with the NRTL model and the binary parameters were obtained.