Liquid-liquid equilibrium of immiscible systems involved in glycerol transesterification with diethyl carbonate

Phase splitting and merging exist in the glycerol transesterification with diethyl carbonate. This work measured the liquid-liquid equilibrium data for two ternary systems (glycerol – diethyl carbonate – glycerol carbonate/ethanol) and one quaternary system (glycerol – diethyl carbonate – glycerol carbonate – ethanol) involved in the glycerol transesterification at various temperatures (343.2 K, 363.2 K, 383.2 K, and 403.2 K) and 1.5 MPa. The equilibrium data were correlated using the NRTL as the activity coefficient model, and the corresponding binary interaction parameters were estimated and validated by checking the consistency of the Gibbs free energy and phase stability for all mixtures in both the immiscible and homogeneous regions. The NRTL model with the regressed parameters could tightly capture the phase equilibrium trends of the systems.