Extraction of Zinc, Silver and Indium via Vaporization from Jarosite Residue

Abstract

Based on technological reasons or in case of indium, which has gained its importance only in recent decades, metals such as zinc, indium and silver can be found in the residues or by-products of the corresponding industry like the iron precipitate—jarosite—from primary zinc production. As a result of low zinc and lead contents, targeted economic recycling of this material has to take into account also the present minor elements, such as indium and silver. In this context, a pyrometallurgical process is investigated which recovers zinc, indium and silver simultaneously as a dust product and the iron as an alloy. The reductive vaporization process is realized by the addition of a second residue, the electric arc furnace dust, acting as a chlorine carrier. Therefore, the paper describes the investigated process development and the achieved recovery rates for the main metals zinc, indium and silver.