A Novel Iron Oxidation Process in Zinc Leaching Solution by Ozone

Abstract

In the zinc hydrometallurgy process, iron is usually present in leach solutions and its elimination is a major operational problem. The first step of iron removal is iron oxidation by MnO2, but this process have some disadvantages such as the cost is relatively high and decreased the current efficiency in the electro-winning stage. In this paper, a new iron oxidation process in zinc leaching solution by ozone oxidation was conducted and evaluated. The results showed that Fe2+ concentration decreased from 7.45 g/L to 0.51 g/L in 80min at pH 3. Oxidation of Fe2+ by O3 is controlled by chemical reaction. O3 dissolve rate, pH and initial iron concentration are key parameters for this process. Our finding indicated the potential application of O3 oxidation in iron removal process of zinc hydrometallurgy.