Synthesising Lead Oxide and Oxychloride Minerals from Spent Lead Acid Battery Waste using a Choline-Chloride based Deep Eutectic Solvent

Lead acid batteries have been successfully recycled with pyrometallurgy for many years. However, this process has historically been associated with mass lead poisonings and continues to contribute significantly to disease burden in developing nations. In this paper a cleaner alternative to pyrometallurgical processing is proposed using deep eutectic solvents (DES) based on choline chloride and oxalic acid to dissolve and convert lead materials into pure lead oxalate which can then be calcined at low temperatures into lead oxide products that can be used for the synthesis of new batteries. We also show that lead oxychlorides can be formed at lower calcination temperatures due to the presence of residual chlorine from the DES.