A novel vacuum distillation method for preparing high purity antimony trisulfide from antimony minerals

Abstract

High purity antimony trisulfide has been widely used in the photovoltaic field. A new clean process for preparing high purity antimony trisulfide directly from antimony ore by a two-step vacuum distillation method at low temperature was proposed in this study. Impurity arsenic was volatilized into the gas phase, and antimony and other impurities were retained in the residue in the first step at 773 K and 5 Pa for 60 min in the first step vacuum distillation. The content of the arsenic in the residue was 0.1 × 10-3 wt%, and the removal ratio was 99.98 %. Antimony trisulfide was volatilized into the gas phase, and other impurities were retained in the residue in the second step vacuum distillation at 923 K and 5 Pa for 30 min. The total removal ratio of impurities through the two-step process can reach 99.524 %, and the antimony trisulfide product with a purity of about 99.99 wt% can be obtained directly. This method provides a novel idea for the efficient and low-cost preparation of high-purity antimony trisulfide.