Study on the flotation behavior and mechanism of ilmenite and titanaugite with sodium oleate

The crystal chemistry and the flotation behavior of ilmenite and titanaugite using sodium oleate collector were investigated. The substitution of Fe3+ and Mg2+ in the crystal structure of ilmenite was identified by X-ray diffraction, scanning electron microscopy/energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy (XPS) analyses; Ti4+ was replaced by Fe3+, and Fe2+ was substituted by Mg2+. The crystal structure of titanaugite consisted of Ca, Mg, Fe, and Ti species. The micro-flotation results showed that ilmenite and titanaugite exhibited good floatability at pH 5.0-8.0, but they had no significant difference. The NaOL adsorption on the ilmenite surface was similar to that of titanaugite at pH 6.0. The results of zeta potential and Fourier-transform infrared spectroscopy analyses indicated that NaOL chemisorbed on the surfaces of ilmenite and titanaugite. The XPS analyses demonstrated that NaOL reacted with Fe and Mg, resulting in ilmenite flotation, whereas NaOL interacted with Fe, Ca, and Mg on the titanaugite surface. The similarity of surface active sites between ilmenite and titanaugite resulted in the non-selective adsorption of NaOL, and the actual mineral flotation obtained only a 42.86% TiO2 grade with 59.79% recovery.