Synthesis and characterization of a novel collector for the desulfurization of fine high-sulfur bauxite via reverse flotation

Bauxite is one of the main raw materials in the alumina industry. Fine high-sulfur bauxite flotation desulfurization is a great challenge presently. This study aims to synthesize nanoparticle collectors (NPCs) by emulsion polymerization to improve the abovesaid flotation desulfurization process. The physicochemical properties of high-sulfur bauxite were analyzed, and the experimental conditions for the synthesis of NPCs were optimized. The interaction mechanism between NPCs and pyrite was studied via fundamental analyses including SEM (Scanning Electron Microscope), FT-IR (Fourier Transform Infrared spectoscopy), Zeta-potential, XPS (X-ray Photoelectron Spectroscopy), and wettability. Under the closed-circuit flotation flowsheet of "one roughing-two cleaning-three scavenging", aluminum concen-trate with a yield of 85.91% and sulfur content of 0.56% were obtained using a common collector. However, with the addition of the novel NPC, aluminum concentrate with a yield of 85.70% and sulfur content of 0.36% could be obtained by a simpler flowsheet of "one roughing-one cleaning-two scav-enging". The improvement in flotation performance is suggested to be contributed by the addition of spherical NPC, which induced a rougher and more hydrophobic pyrite surface.(c) 2022 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.