Effects of ultrasonic pre-treatment on the flotation of ilmenite and collector adsorption. (15th June 2019)

• Record Type: Journal Article
• Authors: Shu, Kaiqian; Xu, Longhua; Wu, Houqin; Fang, Shuai; Wang, Zhoujie; Xu, Yanbo; Zhang, Zhenyue
• Is Part Of: Minerals engineering. Volume 137(2019)
• Page Start: 124
• Page End: 132
• Publication Date: 2019-06-15
• Subjects: Ilmenite -- Sodium oleate -- Ferrous ion -- Ferric ion -- Ultrasonic pre-treatment; Mines and mineral resources -- Periodicals; Ressources minérales -- Périodiques; Mines and mineral resources; Periodicals; Electronic journals; 622
• DOI: 10.1016/j.mineng.2019.04.001
• Languages: English
• ISSNs: 0892-6875

Abstract

Highlights: Sonication remarkably affects ilmenite flotation performance. Sonication increased chemical adsorption of oleate ions on ilmenite surface. Flotation recovery is improved via significant conversion of Fe 2+ to Fe 3+. Possibility of improved selective flotation of ilmenite from gangue minerals. Abstract: Herein we investigate the flotation and possible adsorption mechanism on the surface of ilmenite and the changes in the surface composition of ilmenite before and after ultrasonic pre-treatment through flotation tests, Fourier-transform infrared (FTIR) spectroscopy, zeta potential measurement, X-ray photoelectron spectroscopy (XPS), and microcalorimetry. The flotation results reveal that, under optimum conditions, sonication has a remarkable effect on the flotation of ilmenite. The maximum flotation recoveries of raw and ultrasonically treated ilmenite in the pH range 4–5 are 43.17 and 89.54%, respectively. The zeta potential of the pre-treated ilmenite shifted toward negative values, thus shifting the iso-electric point from pH 6.2 to pH ∼4.2. The FTIR spectra and zeta potential values indicate that the ultrasonic pre-treatment helped enhance the chemical adsorption of oleate ions on the surface of ilmenite. The results of microcalorimetry analysis suggest that the adsorption heat released (−Qads ) from ultrasonically treated ilmenite is more than that released from raw ilmenite. The XPS analysis confirmed that the relative content of Fe 3+ increased from 36.87 to 61.84% following the ultrasonic pre-treatment for 5 min in the pH range 4–5. After the treatment, Fe 2+ ions on the ilmenite surface are abundantly oxidised to Fe 3+ ions. The significant conversion of Fe 2+ to Fe 3+ helped improve the flotation recovery of ilmenite over a wide pH range.