New Pyrometallurgical Bullion Lead Refining Process

After the primary or secondary lead production, the bullion lead is remelted and charged into a vessel with the following refining process. The removal of arsenic, antimony, and tin takes place by salt slags or oxidizing gases like air or pure oxygen. Due to the increasing lead price, Messer Austria GmbH, in cooperation with the Institute of Nonferrous Metallurgy at the University of Leoben, has developed a new process named OXIPOT for the refining of tin, arsenic, and antimony. The OXIPOT process is fundamentally based on purging technology with a ceramic or steel purging device, which leads to an increased retention time of the refining products due to the deeper bath level and optimized specific reaction volume concerning bubble size. This paper describes the process, pilot plant, and thermodynamic calculations for the optimization regarding the selectivity of element removal. Additionally, the study addresses environmental restrictions and economic factors influencing the efficiency of lead refining, focusing on the selectivity refining period of impurities with optimized oxygen partial pressure and the recyclability of formed oxides.