Abstract:By means of molar volumes and infinite-dilution partial molar excess enthalpy of components, interaction parameters of the Wilson equation have been obtained. VLE (vapor-liquid equilibrium) phase diagrams of Sn-X (X=Bi, Cd, Ga, Ge, In, Pb, and Sb) systems at 5 Pa are modeled successfully based on the Wilson equation. The results indicate that the predicted values agree well with the experimental data. It shows that the method could provide effective prediction for the process of vacuum distillation of alloys and theoretical guides for separating and purifying crude metals in cases if the activities of components are not yet known.