Extraction of Useful Products from Copper Pyrometallurgical Slag

摘要

The purpose of this article is to present an innovative idea for pyro-metallurgical copper slag recovery. It includes the following successive processes: (i) Oxidation of the copper slag; (ii) Treatment of the oxidized slag with sodium hydroxide or sodium carbonate under appropriate conditions with subsequent separation of the solid from the liquid phase; (iii) Washing out the solid residue with water. The resulting solid residue is a mixture of iron oxides suitable for use in metallurgy. The liquid part consists of silicon in alkali metal hydroxide solution, which may be turned into silica gel with appropriate subsequent treatments. Basic principles, goals, solutions and results are obtained, enabling the development of a process for obtaining useful products from slag as an attempt at its fully recycling, which may help solving one of the main problems of environmental protection in metallurgy, i.e., reducing the amount of the copper slag.