Patent ID: 7794677
Filing Date: 2010-09-14
Classification: C22B,Y02P

Abstract:
1. A batch method for removing copper from a molybdenite concentrate that contains copper sulfides in the absence of chlorine gas, the method comprising the steps of: a). placing ferrous chloride in an autoclave and converting the ferrous chloride to ferric chloride by reacting the ferrous chloride with oxygen or a combination of oxygen and ozone in the presence of hydrochloric acid at a temperature greater than 100° C. and at a pressure up to 30 bar in order to form a ferric chloride solution; b). adding the molybdenite concentrate that contains copper sulfides as an impurity to the ferric chloride solution in the autoclave in the presence of an additional amount of hydrochloric acid in order to dissolve copper from the copper sulfides at temperature greater than 100° C. and a pressure up to 30 bar thereby forming a slurry of unreacted molybdenite concentrate and a solution that contains copper ions from the dissolved copper sulfides; c). separating the molybdenite concentrate from the solution that contains the copper ions by filtration thereby obtaining a molybdenite concentrate having an amount of copper less than about 0.2% w/w and a clear solution that contains the copper due to the dissolution of copper sulfides.