Alkanesulfonic acid based electrolytes for electro-processing lead

The design of an electrochemical process requires adequate choice of an electrolyte, as physical and chemical properties of the electrolyte impact the efficiency and performance of the electrochemical step. In addition to providing for conductivity and solubility, the electrolyte affects the safety, specificity, and cost of the overall process. In the electro-processing of lead, numerous benefits can be obtained through the use of alkanesulfonic acid based electrolytes. These benefits include; good aqueous solubility of Pb2+ , reasonable stability of group 15 anode slimes, good ambient working conditions, superior inert anode stability, coherent lead deposits, ease of analysis and good electrolyte stability. This report summarizes the basic chemical and physical properties of aqueous alkanesulfonic acid electrolytes, particularly methanesulfonic acid (MSA), with emphasis on properties pertinent to electrochemical processes involving lead. In addition, the development of MSA based lead electrowinning and lead electrorefining processes are covered in some detail. (author)