Removal of zinc oxide with high content of chlorides derived from steel mill electric arc furnace dust

Abstract

This article presents the investigation results of the chloride removal process in high chloride content zinc oxide (ZnO) derived from steel mill electronic arc furnace dust (EAFD) by oxidation-reduction method. The raw material sample is ZnO with a content of Zn 53%, Pb 12%, and Cl 5.2%. The factors affecting the chloride removal efficiency such as pH, solid/liquid ratio, temperature, and reaction time were investigated. The obtained results showed that the chloride removal efficiency reached up to 96% under the following conditions: solid/liquid ratio = 1/10, pH 12, temperature 80oC, and reaction time of 120 mins. The washed ZnO has a zinc content of 55% and the chloride content is reduced to 0.2% by weight. The ZnO raw material, after removing chloride by this method, meets the required standards for the preparation of electrolytes for zinc electrowinning in an alkaline medium to recover metallic zinc powder.