Application of modified molecular interaction volume model for phase equilibrium of PbS–Sb2S3 system in vacuum distillation

In this paper, the modified molecular interaction volume model (M-MIVM) was used to calculate the activities of components of the PbS–Sb2S3 binary matte system. On this basis, the vapor-liquid equilibrium (VLE) data of the PbS–Sb2S3 system were calculated by M-MIVM in combination with the theory of vacuum metallurgy and VLE. Additionally, the VLE experiment of the PbS–Sb2S3 binary matte system was conducted to correctly interpret the results of the model. The calculated results of the VLE of the model were consistent with the experimental values, and the VLE calculation of the PbS–Sb2S3 binary matte system by M-MIVM was reliable. This is an effective and convenient method to predict the relationship between product components with temperature and pressure in vacuum distillation of PbS and Sb2S3 mixed melts, providing theoretical guidance for vacuum separation and purification of PbS and Sb2S3.