Hydrometallurgical processes development for zinc sulphate liquors production for their utilization as feedstocks in electrolytic processes

摘要

This study deals with the development of a hydrometallurgical process for zinc recovery from Waelz oxide. This oxide is a concentrate of zinc and lead oxides obtained pyrometallurgically from EAF dusts. Its main objective is the production of a zinc sulphate liquor to be used as feedstock in electrolytic processes. The process requires different stages to achieve this goal. The first stage consists of a sulphuric leaching. After the leaching, to fulfil the strict requirements of electrolysis feedings, some purifying stages, such as oxidation and cementation, are required in order to remove most of the impurities present in the sulphuric liquor. Finally, if the concentration of some metallic impurity is above the accepted level for electrolytic processes, an additional purification stage could be considered.