The hydrometallurgical extraction of metals from nickel laterite ores has been developed in order to make the process technically and economically feasible. The treatment of leach solutions by different separation techniques have been studied. The primary metal to be recovered from laterite ore is nickel. Other metals of economic interest include cobalt and copper. Copper is very important for the automotive industry and, especially, electronics. Treatment of leach solutions by oxidation and hydroxide precipitation have the main problem of the co-precipitation of other metals. The iron precipitation process from nickel laterite leach solutions leads to metal losses by co-precipitation of copper and cobalt. The aim of this work was to study a selective precipitation of copper through the reduction process. Sodium dithionite was used as a reducing agent. The effect of precipitation time was studied; varying between of 30-120 min. Results showed that 77 % of the precipitate is composed of copper sulfide while, the remaining sulfur arising from the sulfate in the solution and the decomposition of the reducing agent. Analysis of the solution shows that 97 % of the copper precipitates and confirms the possibility of selective copper recovery.
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