Document Type : Original Research Paper
Authors
- Ayman M. Ibrahim 1
- Han Wang 2
- Dianwen Liu 2
- Peilun Shen 2
- Hassan A. Osman 3
- Muhannad Alhaj 4
- Mohamed A. Ibrahim 4
- Misbah Khalil 4
1 State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, Yunnan 650093, PR China
2 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
3 Department of Chemistry, Faculty of Education, University of Nyala, Nyala 63311, Sudan
4 Department of Mining Engineering, Faculty of Engineering Science, Omdurman Islamic University, Khartoum 14411, Sudan
10.22044/jme.2026.17042.3355
Abstract
In this study, Pb²⁺ and STG were used as effective co-activation reagents before sodium sulfide treatment to assess their effect on smithsonite floatability. The flotation test results showed that sodium sulfide nonahydrate (SSN) and sodium diethyl dithiocarbamate (DDTC) concentrations significantly impacted floatability, achieving maximum recoveries of 89.32% and 93.19%, respectively. XPS analysis confirmed that Na₂S treatment introduced sulfur species onto the smithsonite surface, enhancing collector attachment and facilitating the formation of PbS and ZnS. FTIR analysis further substantiated that co-activation enhances DDTC adsorption via C=S vibrations, thereby increasing the number of active sites available for interaction with the collector relative to direct sulfidation. FESEM-EDS and AFM analysis at pH 9 confirmed that co-activation resulted in the formation of denser, cloud-like layers of PbS and ZnS on the surface. These layers improved flotation efficiency, increased hydrophobicity, and strengthened DDTC interaction, thus promoting flotation. Additionally, ToF-SIMS and EPMA analyses indicated higher Pb⁺ and S⁻ intensities in the co-activation system, confirming enhanced surface reactivity and substantiating the increased activity and diversity of sulfidation products. This study offers an effective approach to enhancing smithsonite flotation recovery by optimizing surface chemistry and collector attachment.
Keywords
Main Subjects
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