Application of MIVM for Pb-Sn-Sb ternary system in vacuum distillation

In this paper, the molecular interaction volume model (MIVM) has been used for a calculation of the activities of components of Pb-Sn-Sb ternary alloy system. The separation coefficients of the related binary alloys Sn-Pb and Sn-Sb and the vapor-liquid phase equilibrium of the Pb-Sn-Sb alloy system were also calculated by using the MIVM. Experiments for the separation of the Pb-Sn-Sb ternary alloy were carried out for the proper interpretation of the results of the model. The predicted data are in good agreement with the experimental results, which indicates that MIVM is reliable and convenient since it has certain physical meaning from the viewpoint of statistical thermodynamics and requires only two infinite dilute activity coefficients for each sub-binary system.