Electrochemical recovery and recycling of metals from metal precipitates

A potential process for the recovery of dissolved metal ions from wastewater's and process streams and their recycling as solid metal is described. The process is based on simple precipitation of the metal ion, as either hydroxide or sulphide, the dissolution of the solid precipitate in mineral acid, followed by electrodeposition of the solid metal. The process uses the acid generated during electrodeposition in the dissolution of the metal precipitates. Sulphide used in the process is also recycled. The pertinent features of the process, for example the water balance and acid balance, are analysed. The process cost implications are discussed in conjunction with typical experimental data for dissolution and deposition of tin and copper and lead.