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

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 2-butanone + 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.