Investigation of the efficient separation of tin–antimony alloys via vacuum distillation and stepwise condensation

One major industrial challenge is the extraction of antimony from tin-antimony alloys. This paper presents a procedure for manufacturing tin-antimony alloy using vacuum distillation and step-wise condensation. Tin and antimony can be successfully separated by vacuum distillation, according to theoretical calculations. According to the results, the antimony content declines by around 1.18 wt.% and the residual rate drops by almost 5% when the evaporation temperature rises from 1623K to 1723K.Considering the change in tin content within the volatiles, 1673K selected for industrial tests. Industrial experiments reveal that at an antimony condensation temperature of 863-918K, the Sb content in residual crude tin is 7.12%; volatile I in the primary condensation area contains 75.42% Sb but only accounts for 10.55% of total mass; volatile II in the secondary condensation area has an Sb content of 92.77%, yielding high-quality crude antimony. This paper proposes a continuous vacuum distillation and step-wise condensation process for treating tin-antimony alloy, consuming only 414.53kW·h/t of energy while achieving effective separation of antimony, providing a novel technical solution for this challenge.