Selective precipitation of Cu in manganese-copper chloride leaching liquor

Abstract

Recovery of valuable metal from industrial waste is critically important for wastewater treatment and recycling. In the present work, we developed a new method for selective copper extraction from the actual industrial manganese-copper chloride leaching liquor, which was produced in wet extraction of cobalt. The theoretical pH value for selective copper precipitation was calculated, which was in the range of 2.80–4.71. Manganese carbonate was used for selective copper deposition, and the factors that could affect the precipitation performance were investigated. The procedure for selective precipitation of copper was optimized as follows: the amount of manganese carbonate was twice the theoretical amount of neutralization acid; the reaction temperature and time were 60°C and 4.0h, respectively. Under the optimal conditions, the copper deposition rate was higher than 90%, while the deposition rates of other ions were lower than 10%. The XRD and SEM results showed that the copper-rich precipitate was granular and its main component was Cu2(OH)3Cl.