© 2015 Canadian Institute of Mining, Metallurgy and Petroleum. Selective leaching of lead from a Pb-Ag-Zn concentrate with hydrogen peroxide in citrate solutions was studied at room temperature. Leaching tests were performed, varying the H2O2 concentration and the solid-liquid ratio, holding the solution pH constant at 7 and the citrate concentration at 1M. Lead extractions of 100%were achieved with four and five times the stoichiometric quantity needed to form elemental sulphur, with only a small amount of metal impurities dissolved (Ag, Zn and Fe). The lead solubility limit at those conditions was found to be24 g Pb(II) L-1. X-ray diffraction analyses of the leach residues were free of galena (PbS), while other metal sulphides, such as sphalerite (ZnS), chalcopyrite (CuFeS2) and pyrite (FeS2), were basically unaffected.
Zárate-Gutiérrez, R., Gregorio-Vázquez, L., & Lapidus, G. T. (2015). Selective leaching of lead from a lead-silver-zinc concentrate with hydrogen peroxide in citrate solutions. Canadian Metallurgical Quarterly, 305-309. https://doi.org/10.1179/1879139515Y.0000000020