Patent ID: 6387240
Filing Date: 2002-05-14
Classification: C22B,Y02P

Abstract:
A method for removing sulfur generated in leaching of nickel matte from a leaching cycle of the nickel matte, which method comprises leaching the nickel matte in several steps with an anolyte of a nickel electrolysis to form a nickel sulfate solution; purifying the nickel sulfate solution and subjecting the purified nickel sulfate solution to the nickel electrolysis to recover elemental nickel and the anolyte containing the sulfur of the nickel matte as sulfuric acid; neutralizing part of the sulfuric acid of the anolyte in a neutralization step with a calcium-based neutralizing agent to produce a solution that is saturated with gypsum; and removing gypsum from the gypsum saturated solution before recycling the neutralized anolyte to the leaching cycle.