Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

In this work, experimental solubility data of para-tert-butylbenzoic acid in binary solvents of acetic acid + water (293.15 to 333.15) K, methanol + water (293.15 to 328.15) K and acetic acid + para-tert-butyltoluene (293.15 to 323.15) K, were studied over acetic acid/methanol mass fraction, w2 (on solute free basis) of 0.1 to 0.6 at temperatures of 5 K interval. The solubility measurements showed that acetic acid + para-tert-butyltoluene recorded higher solubility than acetic acid/methanol + water for the same mass fraction of acetic acid at each temperature. Moreover, solubility increases with increase in temperature for the studied binary systems and the acetic acid + para-tert-butyltoluene system presents a maximum solubility effect at mass fraction of 0.2 (0.38 mole fraction) of acetic acid. Several thermodynamic models such as Buchowski-Ksiazczak equation, the Van t Hoff equation, the modified Apelblat equation and NRTL model were fitted to the experimental data and the optimum values of the regressed parameters were presented. The results indicate that the Van t Hoff and modified Apelblat equation represent the experimental findings better compared to other models based on the average absolute percentage deviation (aAAPD).