Patent ID: 8906220
Filing Date: 2014-12-09
Classification: C22B,C25C,Y02P

Abstract:
1. A method for production of metallic cobalt from a nickel solvent raffinate comprising the steps of: (A) adding a sulfide precipitation agent to the nickel solvent extraction raffinate thereby producing a sulfidized pulp at least comprising cobalt sulfide; (B) removing ammonia from the sulfidized pulp; (C) leaching the sulfidized pulp with a leaching solution comprising sulfuric acid to produce a cobalt enriched leaching solution; (D) removing zinc from the cobalt enriched leaching solution by solvent extraction with di-(2-ethylhexyl)phosphoric acid in a solvent wherein the cobalt enriched leaching solution has a pH between 1.4 and 1.8; (E) adding a carbonate precipitation agent to the cobalt enriched leaching solution to precipitate cobalt carbonate; (F) leaching the precipitated cobalt carbonate with an acid to produce an electrolyte solution; and (G) extracting metallic cobalt from the electrolyte solution by electrowinning.