CHLORIDE ASSISTED HYDROMETALLURGICAL EXTRACTION OF NICKEL AND COBALT FROM SULPHIDE ORES

摘要

A process for the extraction of Ni/Co values from an ore orconcentrate comprises the steps of subjecting the ore orconcentrate to pressure oxidation in the presence of oxygen and anacidic solution containing halide, copper and sulphate ions toobtain a liquor containing Ni/Co values from the resultantpressure oxidation slurry. The liquor is subjected to a selectiveprecipitation treatment to obtain a solid containing Ni/Cohydroxide. The solid is subjected to a Ni/Co leaching stage withan ammonium solution to produce a leach solution containing Ni/Covalues and a residue. The Ni/Co values are separated by solventextraction to produce solutions suitable for electrowinning of Niand Co. The process also provides for the recovery of preciousmetals and other metals such as copper.