Hydrometallurgical Technology for Processing of Galvanic Sludges

Abstract

The problem of processing galvanic sludges, formed as a result of neutralization of technological solutions and wastewater containing heavy non-ferrous metals is considered. At present, sludges are transported to disposal area and are not used in any way. Typically, such sludges contain significant amounts of chromium and nickel, which creates environmental hazard. Investigated sludge contains up to 6.6% Ni and up to 7.4% Cr. The hydrometallurgical technology for processing of these sludges has been developed. Solutions of sulfuric acid and ammonia were used as lixiviants. It is shown that when using a solution of sulfuric acid with pH=1.5, extraction of up to 93.3% Cu, 70.2 Ni, 90.3 Zn is achieved. For selective recovery of nickel from leachates the process of sorption concentration by Lewatit TP207 is proposed. © Published under licence by IOP Publishing Ltd.