METHOD FOR MANUFACTURING NICKEL/COBALT MIXED SULFIDE FROM NICKEL OXIDE ORE BY WET SMELTING METHOD

摘要

Provided is a wet smelting method whereby the amount of nickel coprecipitated with impurities is reduced and nickel yield can be increased.　The present invention provides a method for manufacturing a nickel/cobalt mixed sulfide, the method including: a leaching step S1 for performing sulfuric acid leaching of a nickel oxide ore slurry under high temperature and high pressure and obtaining a leached slurry; a solid/liquid separation step S2 for separating a leaching residue from the leached slurry and obtaining a leachate including an impurity together with nickel and coba a neutralization step S3 for sedimentation-separating a neutralized sediment formed by adjusting the pH of the leachate, and obtaining a neutral final liquid including nickel and coba a dezincification step S4 for separating zinc and other sulfides obtained by treating the neutral final liquid with hydrogen sulfide, and obtaining a dezincified final liquid; and a nickel recovery step S5 for recovering a mixed sulfide including nickel and cobalt obtained by treating the dezincified final liquid with hydrogen sulfide; wherein the Fe(III) concentration of the neutral final liquid is adjusted to 0.18 g/L or less.