Predicting effect of dissolved solute on the vapour-liquid equilibria of organic solvent mixtures and aqueous organic acid solutions

Abstract

Application of the Tan model for predicting the vapour-liquid equilibria of mixtures of solvents containing a dissolved solute was extended to organic solvents and aqueous acetic acid solutions saturated with polar and non-polar solutes. The predicted equilibria agreed well with the experimental data. The ratio of the solute-solvent interaction parameters was found to be an effective measure of the salting-in/out effect of the dissolved solute. This study confirms (a) the general applicability of the Tan model for predicting the vapour-liquid equilibria of mixed solvent systems containing a dissolved solute, (b) the validity of using the ratio of solute-solvent interaction parameters as a criterion for salting-in/out effect of the dissolved solute and (c) the relevance of the system of classification of solutes to both polar and non-polar solute-solvent systems regardless of the degree of saturation of the dissolved solute in the system.