A fundamental study of chalcopyrite flotation in sea water using sodium silicate. (1st August 2019)

• Record Type: Journal Article
• Authors: Li, Yubiao; Zhu, Hongjia; Li, Wanqing; Zhu, Yangge
• Is Part Of: Minerals engineering. Volume 139(2019)
• Publication Date: 2019-08-01
• Subjects: Flotation -- Chalcopyrite -- Sea water -- Sodium silicate -- Mg(OH)2; Mines and mineral resources -- Periodicals; Ressources minérales -- Périodiques; Mines and mineral resources; Periodicals; Electronic journals; 622
• DOI: 10.1016/j.mineng.2019.105862
• Languages: English
• ISSNs: 0892-6875

Abstract

Graphical abstract: Highlights: Chalcopyrite flotation recovery was significantly decreased in sea water, primarily due to Mg 2+ . Sodium silicate improved chalcopyrite flotation in sea water and MgCl2 solution, but insignificantly in pure water. SS adsorbed on Mg(OH)2 surface, preventing Mg(OH)2 adsorption on chalcopyrite surface. Electrostatic interaction played an important role in reversing forces between chalcopyrite and Mg(OH)2 . Abstract: Due to the shortage of fresh water, sea water has been considered as a promising alternative for mineral flotation. Sodium silicate (SS) was used to eliminate the negative influence due to the application of sea water for chalcopyrite flotation and the related mechanisms were studied. Flotation results showed that the most detrimental compound in sea water was the divalent ion of Mg 2+ . Contact angle measurements suggested that SS increased chalcopyrite hydrophobicity in sea water and MgCl2 solution. The zeta potential of chalcopyrite became more negative while that of Mg(OH)2 was reversed from positive to negative upon the addition of SS, preventing the adsorption of hydrophilic Mg(OH)2 precipitates on chalcopyrite surface. FTIR and XPS analyses further confirmed that the presence of SS in sea water reduced the adsorption of Mg(OH)2 on chalcopyrite surface. In addition, Derjguin-Landau-Verwey-Overbeek (DLVO) calculation indicated that SS can prevent the adsorption of Mg(OH)2 on chalcopyrite surface, thereby increasing chalcopyrite recovery. Therefore, this study presents an effective method to improve chalcopyrite flotation recovery in sea water.