Extraction of nickel, cobalt and iron from laterite ores by mixed chloride leach process.

A new process developed for the production of base metals Ni, Co and Fe, based on chloride hydrometallurgy, is applicable to both high- and low-iron laterite ores. The process comprises atmospheric leaching in mixed HCl-MgCl2 media to bring Fe, Ni, Co and Mg into solution, solvent-extraction steps to generate high-purity pregnant stripping solutions of Fe, Ni and Co individually, precipitation of high-purity Ni and Co products by addition of MgO generated from pyrohydrolysis, production of Fe2O3 and regeneration of HCl by pyrohydrolysis of the iron chloride-rich pregnant stripping solution, production of MgO and regeneration of HCl by pyrohydrolysis of bleed stream from the MgCl2-containing raffinate from the nickel sovent-extraction stage, and recycling of the HCl generated by pyrohydrolysis. A comparison of this process with commercial laterite processes - Caron process, high-pressure acid-leach process and pyrometallurgical process - is additionally presented.
A new process developed for the production of base metals Ni, Co and Fe, based on chloride hydrometallurgy, is applicable to both high- and low-iron laterite ores. The process comprises atmospheric leaching in mixed HCl-MgCl2 media to bring Fe, Ni, Co and Mg into solution, solvent-extraction steps to generate high-purity pregnant stripping solutions of Fe, Ni and Co individually, precipitation of high-purity Ni and Co products by addition of MgO generated from pyrohydrolysis, production of Fe2O3 and regeneration of HCl by pyrohydrolysis of the iron chloride-rich pregnant stripping solution, production of MgO and regeneration of HCl by pyrohydrolysis of bleed stream from the MgCl2-containing raffinate from the nickel sovent-extraction stage, and recycling of the HCl generated by pyrohydrolysis. A comparison of this process with commercial laterite processes - Caron process, high-pressure acid-leach process and pyrometallurgical process - is additionally presented.