New insights for improving ilmenite flotation via surface modification with lead ions

Abstract

In order to further investigate the mechanism of lead ions in activation ilmenite flotation, the adsorption behaviour of lead ions on ilmenite surface was deeply illustrated using the combination of adsorption amount, zeta potential, inductively coupled plasma mass spectrometry (ICP), energy-dispersive X-ray spectroscopy Mapping (EDS-Mapping), and X-ray photoelectron spectroscopy (XPS) in this study. The results revealed that lead ions activated the ilmenite flotation by promoting the adsorption of sodium oleate. This promotion impact could be attributed to the positive shift of surface charge and the increase in surface active sites after lead adsorption. The changes transferred the adsorption mode of sodium oleate on ilmenite surface into electrostatic adsorption and chemisorption involving double active site (Pb, Fe). The Pb(OH)+ was certified as the main active species on activating ilmenite flotation through the analysis of lead adsorption amounts and solution chemistry. Furthermore, the EDS-Mapping and XPS high-resolution spectra analysis evidenced that the Pb(OH)+ adsorbed onto the surface sites of O, Fe, and Ti on ilmenite surface by resorting the bridging action of the O atom.