Novel depressant-driven flotation of chalcopyrite and molybdenite: A synergistic strategy for selective depression and sustainable separation

Abstract

Efficient and environmental friendly separation of chalcopyrite and molybdenite has always been a difficult problem in mineral processing. Therefore, a new strategy using mercaptosuccinic acid (MSA) as chalcopyrite depressant has been proposed in this study, based on the heterogeneous surface regulation by copper ions on mineral surfaces. The MSA dosage required for chalcopyrite-molybdenite separation reduced significantly after heterogeneous surface regulation of copper ions. Molybdenite concentrate with Mo grade of 53.97% and recovery of 89.81% can be obtained with less MSA in mixed-mineral flotation. TOC, XPS and ToF-SIMS results demonstrated that the heterogeneous surface regulation of copper ions significantly increased the adsorption capacity of MSA on chalcopyrite surface, while the adsorption of MSA on the surface of molybdenite was negligible. XPS, ToF-SIMS and DFT calculations indicated that MSA interacts with the copper sites on the chalcopyrite surface through the carboxyl group in its molecule, and the interaction is attributed to the p orbital of the oxygen atom and the d orbital of the copper atom. The findings provide valuable insights into the enhancement of organic depressant performance via metallic ion regulation at mineral surfaces, which holds significant reference implications for efficient separation and environmental protection in mineral processing.

Keywords

copper ions / heterogeneous surface regulation / mercaptosuccinic acid / chalcopyrite / efficient separation

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Central South University