An original strategy for efficient flotation recovery of smithsonite: Coactivation performance and mechanism

Abstract

In this work, Cu²⁺ and Pb²⁺ were employed as activators to explore the differences in the changes of smithsonite surface properties and sulfidization process. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectroscopy (ToF-SIMS) results showed that more active Cu and Pb components were formed on the smithsonite surface in the Cu-Pb coactivation system, which provided favorable conditions for the subsequent adsorption of Na₂S and collectors. Additionally, the Cu−S and Pb−S products coexisted on the smithsonite surface in the Cu-Pb coactivation system, and the signals of Cu, Pb and S were more pronounced. Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM) results further proved that more sulfidized products were discovered on the smithsonite surface after Cu-Pb coactivation, which indicated that the sulfidization process was enhanced. The Fourier transform infrared (FTIR), contact angle test, and collector adsorption, molecular dynamics simulation showed that the KAX adsorption behaviour was improved after Cu-Pb coactivation, which achieved the higher hydrophobicity of smithsonite surface. Therefore, the Cu-Pb coactivation could significantly enhance the surface reactivity of smithsonite, and improve the adsorption behaviour of sulfidizing reagents and collectors, thus effectively increasing the smithsonite hydrophobicity. The results of flotation showed that the Cu-Pb coactivation significantly improve the smithsonite flotation recovery, which increased up to 96.13 %. The results of this work provided a new flotation process for the efficient flotation of zinc oxide ores.