Welan gum as a new depressant for the flotation separation of chalcopyrite from talc

Abstract

Taking chalcopyrite and talc as examples, this article explores an anionic polysaccharide polymer, Welan gum (WLG), as an environmental depressant of talc. It depresses talc in the flotation system, thereby improving the flotation index of chalcopyrite. The flotation test results showed that under the action of an 80 mg/L depressant, a chalcopyrite concentrate with Cu grade of 28.87 % and Cu recovery rate of 86.72 % was obtained, indicating efficient separation ability of chalcopyrite-talc. The zeta potential and adsorption results indicate that the adsorption capacity of WLG on the surface of chalcopyrite is significantly lower than that on the surface of talc. The contact angle tests found a significant change in the wettability of talc after the action of depressants. Fourier-transform infrared spectrum (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope energy spectrum spectroscopy (SEM–EDS) studies have found that WLG is mainly adsorbed on talc through physical interactions. According to density functional theory (DFT) calculation analysis, the –COOH- and –OH in the WLG structure can interact with Mg, Si, and O atoms in talc.