Vapour–liquid equilibria in the binary and ternary mixtures of methyl benzoate, methyl p-toluate and dimethyl terephthalate

Low pressure isobaric T–x–y data were determined for methyl benzoate–methyl p-toluate, methyl benzoate–dimethyl terephthalate and methyl p-toluate–dimethyl terephthalate systems at 6.6 and 13.3 kPa, as well as for some methyl benzoate–methyl p-toluate–dimethyl terephthalate ternary mixtures at 6.6 kPa. Both vapour pressures of two pure components and P–x isotherms for all three binaries at 433.15 K were also measured. The ebulliometer-type equilibrium still with manostat and an additional thermostat was used in all measurements. Liquid and vapour compositions were determined by g.l.c. Experimental equilibrium data were fitted to Redlich–Kister, Wilson, NRTL and UNIQUAC equations. Some predictions with UNIFAC method were also made.