Understanding the roles of Na2S and Pb(II)in the flotation of hemimorphite. (September 2017)

• Record Type: Journal Article
• Authors: Jia, Kai; Feng, Qiming; Zhang, Guofan; Shi, Qing; Chang, Ziyong
• Is Part Of: Minerals engineering. Volume 111(2017)
• Page Start: 167
• Page End: 173
• Publication Date: 2017-09
• Subjects: Hemimorphite -- Flotation -- Sulfidization -- Lead ion activation -- XPS -- XRD; Mines and mineral resources -- Periodicals; Ressources minérales -- Périodiques; Mines and mineral resources; Periodicals; Electronic journals; 622
• DOI: 10.1016/j.mineng.2017.06.010
• Languages: English
• ISSNs: 0892-6875

Abstract

Highlights: Hemimorphite flotation using the "Na2 S-Pb(II)-xanthate" process was studied. The "Na2 S-Pb(II)-xanthate" process is an effective method. Amorphous or poorly structured ZnS was formed through sulfuration reaction. A film of PbS, similar to the natural galena, was generated after Pb(II) activation. Abstract: The mechanisms involved in hemimorphite flotation using the "Na2 S-Pb(II)-xanthate" process, including pre-sulfurization using sodium sulfide, activation by lead cations and subsequent flotation using a butyl xanthate collector, were studied. X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS), and X-ray diffraction (XRD) characterization were conducted to identify the mechanism of interaction of Na2 S and Pb(II) with hemimorphite particles. The results indicated that the "Na2 S-Pb(II)-xanthate" process is an effective method for the flotation of hemimorphite, and the maximum recovery of the hemimorphite concentrate increased from 40% to 90%. Hydrosulfide ions were chemisorbed or participated on the hemimorphite ore surface, and a layer of ZnS was formed. The XRD results indicated that the ZnS layer was amorphous or poorly crystallized. PbS was generated by the interaction of Pb(II) with ZnS through an ion-exchange mechanism, which was verified by XPS, SEM-EDS and XRD. The XRD study indicated that the new PbS phase formed on the hemimorphite ore surface was well-crystallized "synthetic galena" with good floatability, which is critical for the potential application of hemimorphite flotation using the "Na2 S-Pb(II)-xanthate" process.