The study of solid-liquid equilibrium for dimethyl terephthalate (DMT) in several solvents from T = (298.15 to 330.15) K

By the gravimetric method, the solubility of dimethyl terephthalate (DMT) is measured in eight monary solvent and one binary solvent (methanol-ethanol) at atmospheric pressure from T = (298.15 to 330.15) K. Obviously, the increase of temperature promotes the increase of solubility in each solvent, while the increase of methanol composition leads to the opposite result in methanol-ethanol. Simultaneously, associating the measured data with seven solid-liquid equilibrium models separately to obtain model parameters, the correlation results show that measured data and calculated data are in good consistence. Especially, the Apelblat and λh have the best agreements for the monary and binary solvents respectively. Furthermore, thermodynamic parameters such as entropy, enthalpy and Gibbs free energy of DMT dissolution are acquired, which proves that the DMT dissolution is an enthalpy-driven, irreversible and endothermic process in every tested solvents.