Keywords
hydrometallurgy
microwave-assisted leaching
copper recovery
gold recovery
thiourea
How to Cite
Abstract
This study investigates the comprehensive processing of copper-smelting slag as a secondary source of valuable and strategically important metals. The chemical and mineralogical characteristics of the investigated material were determined using instrumental analytical methods, including elemental and X-ray diffraction analyses. The results showed that iron was the dominant component, while copper, zinc, sulfur, lead, antimony, silver, tin, and gold were also present. Fayalite and ferrosilite were identified as the principal mineral phases, together with zinc ferrite, copper sulfide, bornite, and sphalerite. The influence of mechanical grinding and microwave-assisted treatment on the subsequent leaching of valuable components was investigated. Leaching experiments demonstrated that combined microwave activation before and during leaching improved the dissolution of copper and other components. Copper recovery reached approximately 91%, while zinc and iron recoveries were about 87.2% and 90.4%, respectively. The residual material was subsequently treated with thiourea to recover gold. The maximum gold recovery of 88.6% was achieved at 60 °C. The obtained results demonstrate the potential of combining mechanical activation, microwave-assisted leaching, and thiourea treatment for the comprehensive utilization of copper-smelting slag.
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Copyright (c) 2026 Xasanov, S.R. (Author)