An investigation of the mechanism of using iron chelate as a collector during scheelite flotation. (15th January 2019)

• Record Type: Journal Article
• Authors: Zhao, Chen; Sun, Chuanyao; Yin, Wanzhong; Luo, Binbin
• Is Part Of: Minerals engineering. Volume 131(2019)
• Page Start: 146
• Page End: 153
• Publication Date: 2019-01-15
• Subjects: Fe-BHA chelate -- Scheelite flotation -- Chemical adsorption -- Electrostatic adsorption; Mines and mineral resources -- Periodicals; Ressources minérales -- Périodiques; Mines and mineral resources; Periodicals; Electronic journals; 622
• DOI: 10.1016/j.mineng.2018.11.009
• Languages: English
• ISSNs: 0892-6875

Abstract

Graphical abstract: Highlights: An iron chelate reagent was developed for scheelite flotation. The best BHA/Fe molar ratio was found as 1.17–1. The possible spatial structure of the Fe-BHA chelate was provided. The flotation mechanism of the Fe-BHA chelate was studied. Abstract: The use of lead ions in combination with benzohydroxamic acid (BHA) as a collector is commonly adopted to modify the surface properties of tungsten minerals to improve their floatability. However, the dosage of lead ions is difficult to precisely control, causing excess dissociative lead ions in the pulp that can consume BHA and lead to a reduction of flotation efficiency. This paper develops a new iron chelate reagent that consists of ferric chloride (FeCl3 ) and BHA by changing the conventional dosing sequence of FeCl3 . The individual mineral flotation results showed that the Fe-BHA chelate had a better scheelite collecting ability compared to the Pb-BHA or Al-BHA chelate, and it proved to be superior to the BHA using Fe 3+, Pb 2+, and Al 3+ as activators. The Fe-BHA chelate also showed a good separation performance in the artificially mixed mineral flotation tests of scheelite and calcite at pH 8.0, as well as of scheelite and fluorite at pH 11.0. The zeta potential measurement results showed that the Fe-BHA chelate altered the zeta potential of scheelite to more positive values compared to the BHA with Fe 3+ ions as activators at pH 8.0–12.0. The FTIR analysis verified the chemical adsorption of the Fe-BHA chelate on the scheelite surface. By conducting Freundlich fitting of the adsorption isotherm of the Fe-BHA chelate on scheelite, the adsorption of Fe-BHA is demonstrated to be an ion-molecule co-adsorption. The potential of the Fe-BHA chelate as a scheelite collector is also proven.