Adsorption mode of sodium citrate for achieving effective flotation separation of ilmenite from titanaugite

Sodium citrate was introduced as a depressant for ilmenite flotation, and its effect on the activation of ilmenite and depressing titanaugite was investigated. The flotation results showed that ilmenite was effectively separated from titanaugite as a concentrate with a TiO 2 grade of 43.62% and recovery of 87.42%. The contact angle analysis revealed that sodium citrate further increased the hydrophobicity of ilmenite and decreased it in the case of titanaugite. The zeta potential results indicated that the adsorbed sodium citrate accelerated the adsorption of sodium oleate on the ilmenite surface, but weakened the adsorption on titanaugite. Inductively coupled plasma mass spectrometry (ICP) and solution chemistry analyses illustrated that sodium citrate improved the flotation of ilmenite and depressed the flotation of titanaugite. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis demonstrated that sodium citrate adsorbed onto ilmenite through Fe 3+ and onto titanaugite through the active sites of Ca and Mg.