Solid–liquid equilibria of selected ternary systems containing diphenyl carbonate, alcohol, dialkyl carbonate, and phenol

Abstract

We studied the solid–liquid equilibria (SLE) of five ternary systems for application to the purification of diphenyl carbonate (DPC) during crystallization. These systems contained DPC, alcohol, dimethyl carbonate (DMC), diethyl carbonate (DEC), and phenol, i.e., ethanol + DEC + DPC, methanol + DMC + DPC, phenol + DMC + DPC, ethanol + phenol + DPC, and DEC + phenol + DPC. The SLE data of these ternary systems were experimentally determined at atmospheric pressure and temperatures of approximately 245 – 352 K. The SLE measurements of the ternary systems were made for pseudo-binary systems by varying the value of the mole fraction (on a DPC-free basis) of one component of the binary system. The melting points were experimentally determined using a synthetic, visual technique we designed in a previous study. The experimental SLE data of the ethanol + DEC + DPC and methanol + DMC + DPC systems were compared with the predictions of the nonrandom two-liquid model based on binary interaction parameters determined for the constituent binary systems. The predictions of the NIST modified UNIFAC group contribution method were also assessed.