A novel sulfidization system for enhancing hemimorphite flotation through Cu/Pb binary metal ions

The low reactivity of hemimorphite surfaces hinders the effective action of sulfidizing agents and xanthate, resulting in unsatisfactory flotation performance. To enhance the surface reactivity of hemimorphite with sulfidizing agents and xanthate, Cu/Pb binary metal ions were introduced into the sulfidization flotation system to enhance the sulfidization process and thereby promote hemimorphite flotation. The flotation results demonstrated a remarkable improvement in the hemimorphite flotation recovery when Cu/Pb binary metal ions were added prior to sulfidization. The flotation recovery of hemimorphite increased from less than 5% to over 80%. After strengthening the sulfidization of hemimorphite with Cu/Pb binary metal ions, the mineral surface formed multicomponent sulfide products composed of zinc, copper, and lead sulfide. The reactivity of the copper-lead sulfide components exceeds that of the zinc sulfide component; thus, the enhancement by Cu/Pb binary metal ions not only increases the content of sulfide products on the hemimorphite surface but also augments their reactivity. Contact angle and adsorption experiments indicated that after enhanced sulfidization with Cu/Pb binary metal ions, the hemimorphite surface adsorbed a greater amount of xanthate, significantly increasing the mineral surface hydrophobicity. Consequently, the enhanced sulfidization by Cu/Pb binary metal ions effectively improved the flotation behavior of hemimorphite, presenting an innovative sulfidization system for the flotation recovery of zinc silicate minerals in zinc oxide ores. (c) 2024 Published by Elsevier B.V. on behalf of China University of Mining & Technology. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).