Solubility behavior of mixtures containing refined soybean oil and low-toxic solvents at different temperatures

Abstract

Solubility behavior of refined soybean oil (RSO) plus seventeen low toxic solvents was determined experimentally, and was predicted using five versions of the UNIFAC method. Qualitative results obtained by cloud point detection at a temperature T of 278.15 K showed that eleven systems were completely miscible, two formed stable emulsions, and four resulted in biphasic mixtures. Mutual solubility at different temperatures of pseudobinary partially miscible systems (RSO plus solvent) was measured either by the cloud point method or by direct tie line quantification: RSO plus anhydrous ethanol, or acetic acid, or ethyl lactate, or dimethyl sulfoxide (DMSO). Liquid-liquid equilibrium data were satisfactorily correlated by the NRTL and UNIQUAC models, which were also used for determining the upper critical solution temperatures (UCST) by liquid-liquid flash calculations. Further, the predictive capacity of five versions of the UNIFAC method was verified and comparisons among them were achieved