Recovery of nitric acid soluble transition metals from sulfur and iron containing ores of the same

Abstract From the Canadian patent

This invention relates to a process of recovering copper from a sulfur and iron containing ore of the same. The process consists of the steps of a) forming an aqueous nitric acid leach solution of the ore; b) heating the solution under containment to a temperature at or above the melting point of sulfur to establish an iron content of no greater than 15 grams of iron values per liter in the leach liquor; c) adding an acid neutralizer to the liquor to establish a pH of about 1-2 therein and to produce salts of the acid which are soluble in the liquor; d) contacting the liquor with a copper specific aqueous insoluble organic extractant liquid while maintaining the foregoing pH in the liquor …