Artemisia sphaerocephala krasch gum for selective pyrite depression in chalcopyrite flotation: Interfacial reaction and application research

This study investigates the use of artemisia sphaerocephala krasch gum (ASKG) as a biocompatible pyrite depressant to effectively achieve the flotation of chalcopyrite. The flotation performance of pyrite and chalcopyrite treated with ASKG was investigated through micro-flotation tests, and the interaction mechanism between ASKG and pyrite was systematically studied using various characterization techniques. Micro-flotation results showed that ASKG effectively depresses the flotation of pyrite at pH 8, while its effect on chalcopyrite flotation is negligible. Mixed-mineral micro-flotation tests further demonstrated that, under pH 8.0, the addition of 60 mg/L ASKG and 60 mg/L sodium butyl xanthate (SBX) resulted in a recovery rate of chalcopyrite in the froth product that was 60.46 % higher than that of pyrite. Contact angle measurements and Fourier-transform infrared spectroscopy (FTIR) revealed that ASKG preferentially adsorbs on pyrite rather than on chalcopyrite, and the pre-adsorbed ASKG hinders the subsequent adsorption of SBX on pyrite. X-ray photoelectron spectroscopy (XPS) and molecular dynamics (MD) simulations further confirmed that the –OH group in ASKG acts as the active group interacting with the pyrite surface, forming chemical chelation with ferric hydroxide on the pyrite surface. In conclusion, ASKG shows potential as a pyrite depressant for the selective flotation of chalcopyrite.