Liquid Phase Equilibria of Water + Formic Acid + Dimethyl Carbonate Ternary System at Several Temperatures

Liquid–liquid equilibria of water + formic acid + dimethyl carbonate have experimentally been specified at (298.2, 308.2, and 318.2) K. Each phase diagram was obtained by specifying binodal curves and tie-lines. The reliability of the experimental tie-lines was verified via the Othmer–Tobias correlation. The experimental tie-line data were correlated using the nonrandom two liquid and the universal quasichemical (UNIQUAC) models in order to obtain the binary interaction parameters. However, UNIQUAC functional-group activity coefficients (UNIFAC) and modified-UNIFAC methods were also used to predict the phase equilibrium in the system determined from experimental data using the interaction parameters between CH 3, OCOO, HCOOH, and H 2 O functional groups. Distribution coefficients and separation factors were evaluated for the immiscibility region.