Adsorption of polystyrenesulfonate on titanaugite surface: Experiments and quantum chemical calculations

The depression of titanaugite is one of the key challenge in the ilmenite flotation due to their similar natural hydrophobicity. This paper focus on the adsorption performance of new depressant sodium polystyrenesulfonate (SP) on titanaugite surface through experiments and quantum chemical calculation. XPS results illustrates that SP is chemically adsorbed on the titanaugite surface through the interaction of the sulfo groups with the atoms of AL Fe, Ca, and Mg on the titanaugite surface. Also, Al element shows the greatest content decrease 5.12% and Fe/Mg/Ca took the second place, indicating the Al atoms are the main interaction sites for SP adsorption. Quantum chemical calculation shows that the binding energy of SP with the above four metal atoms are in the sequence of Al > Fe > Mg > Ca, suggesting Al as the main interaction site with SP, with the same conclusion with XPS results. The micro flotation results verifies that SP is qualified for the selective depressant of titanaugite for ilmenite/titanaugite separation, which may base on the fact that Al atoms are presence on titanaugite but absence on ilmenite surface. Based on these findings, a suggested model for SP depressing titanaugite flotation was proposed and displayed in detail. (C) 2020 Elsevier B.V. All rights reserved.