Degradation mechanism of surface hydrophobicity by ferrous ions in the sulfidization flotation system of smithsonite

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 648; p. 129119
• Main Authors: Feng, Qicheng, Zhao, Guanghu, Zhang, Ga, Zhao, Wenjuan, Han, Guang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.09.2022
• Subjects: adsorption; contact angle; Fe2+ species; hydrophobicity; infrared spectroscopy; mass spectrometry; pulp; Smithsonite; sulfides; Sulfidization flotation; Surface hydrophobicity; X-ray photoelectron spectroscopy; zeta potential; Smithsonite; Surface hydrophobicity; Sulfidization flotation; Fe2+ species
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2022.129119

Metal ions commonly exist in the flotation pulp, which will affect the mineral surface properties and lead to a change in the mineral floatability. In this work, the effect of Fe2+ on the flotation behavior of smithsonite was investigated, and the interaction mechanism of Fe2+ with the smithsonite surface in the sulfidization flotation system was clarified. The results of microflotation tests showed that the presence of Fe2+ can greatly reduce the flotation recovery of smithsonite. The results of zeta-potential measurement, time-of-flight secondary-ion mass spectrometry, and X-ray photoelectron spectroscopy indicated that addition of Fe2+ before sulfidization generated FeOOH species and hindered formation of active sulfide species on smithsonite. The results of infrared spectroscopy and contact-angle measurement showed that addition of Fe2+ was harmful for adsorption of the collector on smithsonite, and it was difficult to obtain hydrophobic smithsonite surfaces in the Fe2+–sulfidization–xanthate flotation system. Considering the above results, the presence of Fe2+ depressed adsorption of sulfide ions and the collector on smithsonite, making smithsonite show poor floatability, and it was difficult to obtain the ideal flotation recovery of smithsonite. [Display omitted] •Fe2+ an generate iron species with spatial depth on the smithsonite surface.•Addition of Fe2+ decreased the number of active sites on the smithsonite surface.•The content of sulfide on the smithsonite surface decreased after addition of Fe2+.•Adsorption of xanthate on the smithsonite surface was hindered by Fe2+.