Measurement and Correlation of Liquid–Liquid Equilibrium Data for the Extraction of Glycerol Carbonate from Glycerol Using Ethyl Acetate and 2-Butanone + Benzene Mixture

Abstract

Glycerol carbonate prepared by transesterification is a value-added glycerol derivative that can be used as a solvent, electrolyte, and polymer monomer. Due to the high boiling points of glycerol and glycerol carbonate, their separation by distillation is energy-intensive. To evaluate the feasibility of extractive separation of glycerol carbonate with glycerol, ethyl acetate and 2butanone + benzene mixture were selected as the extractants, and the corresponding liquid−liquid equilibrium data were measured at 303.2, 313.2, and 323.2 K under atmospheric pressure. While ethyl acetate provided high extractive selectivity, the distribution coefficient of glycerol carbonate in it was less than one. The 2-butanone + benzene mixture with suitable ratios resulted in more feasible and balanced distribution coefficients and selectivities. The NRTL model was used to correlate the equilibrium data to estimate the interaction parameters, and the quality of the obtained parameters was validated. The NRTL model with the regressed parameters can reproduce the phase equilibrium trend of all of the studied systems.