Harmless, industrial vacuum-distillation treatment of noble lead

Abstract

This paper introduces a new process to process noble lead by vacuum distillation, which is produced from the fire reduction smelting of lead anode slime with a large number of valuable and precious metals. Lead anode slime is important as a raw material for the extraction of precious metals. However, some of the shortcomings of the traditional process, such as serious pollution, complex processes, large resource consumption, and low metal recovery rate, must be overcome. Based on a study of the saturated vapor pressure in the metal and vapor–liquid equilibrium diagram of a binary system, we carried out a large-scale recovery experiment for bismuth and lead with the enrichment of silver and copper. The experimental results show that the copper and silver contents in the residue are higher than 80%. Secondary continuous vacuum distillation resulted in a residue with a Ag content of less than 20 g/t. At the same time, the direct yield of silver from the whole process is higher than 99%, and the evaporation contents of Pb and Bi are above 90%. Achieved a comprehensive recovery of valuable metals recycling.