Prediction of interfacial tensions of binary and ternary liquid-liquid systems by using UNIQUAC Excess Gibbs Free energy model

Interfacial tension of both 36 binary and 6 ternary liquid-liquid systems at 298 K, has been predicted through a reliable thermodynamic model. To properly predict interfacial tension, it is necessary to calculate interfacial area of each constituent of the mixtures. For such estimation, two empirical correlations have been proposed for binary mixtures whose one component is water and experimental data have been used to calculate interfacial area of ternary mixtures. The UNIQUAUC Excess Gibbs Free energy model and its parameters have been used to calculate the concentration and activity coefficients in the bulk and interface phases. The overall average deviation of the predicted binary interfacial tensions is 1.84 mN/m. For other 6 ternary systems, the overall average predictions of the predicted ternary interfacial tensions found to be 1.98 mN/m. In comparison with other methods, these deviations are more accurate.