Surface Enrichment in Malachite Sulfurization Flotation: Adsorption Mechanisms and Performance Optimization

M. Ibrahim, Ayman; Wang, Han; Mekawi, Nazar; A. Yousif, Jaber; Adam, Emadeldin; Alnoor, Alfarouq; Kabashi, Mohammed; Liu, Dianwen

doi:10.22044/jme.2025.16134.3115

Document Type : Original Research Paper

Authors

¹ State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal Resources, Faculty of Land Resources Engineering, Kunming University of Science and Technology, Kunming 650093, Yunnan, PR China

² Department of Mining Engineering, Faculty of Engineering Science, University of Nyala, Nyala 63311, PR Sudan

³ Department of Mining Engineering, Faculty of Engineering, University of Khartoum, Khartoum 11115, PR Sudan

⁴ Department of Mining Engineering, Faculty of Engineering, Eldaein University, Eldaein 63312, PR Sudan

⁵ Department of Mining Engineering, Faculty of Engineering Science, Omdurman Islamic University, 14411, Khartoum, PR Sudan

10.22044/jme.2025.16134.3115

Abstract

This work investigates the surface enrichment of malachite during sulfurization flotation to enhance copper recovery. The goal is to improve flotation efficiency by modifying malachite’s surface properties through sulfurization, using sodium sulfide as the sulfurizing agent. The effects of pre-treatment reagents on flotation recovery were evaluated, focusing on their impact on the surface chemistry of malachite. The findings indicated that malachite treated with ammonium sulfate ((NH₄)₂SO₄) exhibited superior flotation recovery compared to ammonium phosphate ((NH₄)₃PO₄), achieving an optimal recovery rate of 87.5%. FESEM-EDS and ToF-SIMS analyses revealed a significant increase in sulfur species on the surface, promoting the formation of copper sulfide (CuS) films and enhancing the mineral's reactivity during flotation. Theoretical solution chemistry calculations corroborated these findings, showing that ammonium salt treatments facilitate the formation of copper-ammonium complexes, stabilizing copper ions in solution and preventing their precipitation as copper hydroxides or carbonates. By maintaining copper in a stable reactive form, these complexes improve flotation efficiency. Both theoretical calculations and experimental observations confirm that stabilizing copper ions is crucial for enhancing flotation, ensuring copper remains available for interaction with flotation reagents and ultimately, improving copper recovery. The integration of theoretical and experimental approaches enhances the understanding of the sulfurization process and provides an optimized method for improving flotation performance and copper recovery.

Keywords

Main Subjects

Mineral Processing

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Journal of Mining and Environment

Surface Enrichment in Malachite Sulfurization Flotation: Adsorption Mechanisms and Performance Optimization

References

References

Volume 16, Issue 6
September and October 2025
Pages 1881-1895

Surface Enrichment in Malachite Sulfurization Flotation: Adsorption Mechanisms and Performance Optimization

References

References

Volume 16, Issue 6September and October 2025Pages 1881-1895

Volume 16, Issue 6
September and October 2025
Pages 1881-1895