Salt effects on vapour-liquid equilibrium of acetone-methanol system

The effect of NaSCN at salt mole fractions 0.01-0.13 and at saturation on VLE of the binary acetone-methanol system has been investigated experimentally at 101.32 kPa using a modified Othmer equilibrium still. The experimental data were correlated by the electrolytic NRTL model (Mock et al., 1986), the extended UNIQUAC equation (Sander et al., 1986) and the modified Wilson and NRTL models proposed by Tan (Tan, 1985; Tan, 1987; Tan, 1990). The results were compared with those obtained by Tan's predictive models. The salt investigated in this work exhibited both salting-out and salting-in effects on acetone, and experimental data were interpreted by the theory of preferential solvation. An apparent crossing-point between the dew point and the bubble point curves was found at salt mole fractions between 0.01 and 0.09. Experimental and calculated results were compared with those of NaI described previously.