Mechanism research on the influence of microwave activation on the flotation of ilmenite

Through the flotation test of pure minerals, it was found that the flotation effect of ilmenite was better than that of single reagent when OHA and HDPA were used in a molar ratio of 3 : 1. Microwave pretreatment can selectively enhance the floatability of ilmenite.After 120 s treatment, the recovery rate is increased by 5.31 %, and the amount of collector is reduced by 28.57 %, but it has no significant effect on quartz. By means of X-ray diffraction spectroscopy, scanning electron microscopy and energy dispersive spectroscopy, X-ray photoelectron spectroscopy and specific surface area and pore test ,it was found that microwave treatment did not change the phase of ilmenite, but caused the weakening of the crystal plane structure, the formation of microcracks and pores on the surface, showing a similar 'erosion 'morphology. The specific surface area increased from 0.2537 m2/g to 0.4557 m2/g, indicating that the specific surface area of ilmenite could be effectively increased, which provided more active adsorption sites for the adsorption of collectors, which was beneficial to adsorb more collector molecules, increase the adsorption density, and improve the hydrophobic properties of ilmenite surface to a greater extent. XPS results further showed that Fe2+ on the surface was partially oxidized to Fe3+, and the content of Fe3+ increased from 23.91 % to 38.64 %. As a better coordination center, Fe3+ forms a more stable and denser hydrophobic layer with chelating collectors OHA and HDPA, which significantly improves the flotation efficiency and reduces the reagent consumption.