Flotation performance and adsorption mechanism of monazite after the transformation of hydrogen-based mineral phase by octyl hydroxamic acid

This study investigated the laws affecting flotation properties of monazite minerals after roasting pretreatment. The flotation performance and adsorption mechanism of monazite after roasting were investigated systematically through simulation tests, which included micro-flotation tests, Brunauer–Emmett–Teller (BET) analysis, contact angle measurement, zeta potential analysis, scanning electron microscopy energy dispersive spectroscopy, Fourier transform infrared analysis, X-ray photoelectron spectroscopy, and DFTB+. The results of the microflotation tests indicated that octyl hydroxamic acid (OHA) had a superior recovery effect on monazite at a pH of ∼9. The flotation performance of OHA on monazite was significantly better than those of salicylhydroxamic acid (SHA) and benzohydroxamic acid (BHA) under the same conditions. A molecular model of monazite after roasting was simulated and structurally optimized using DFTB+. The adsorption energies were calculated for SHA, BHA, and OHA, which confirmed the strong and stable adsorption of OHA on the surface of monazite after roasting. [Display omitted] •OHA has better trapping effect than BHA and SHA.•OHA adsorbed with monazite roasting products to form new CeO bonds.•OHA recovered 97.38 % of monazite roasted products.•Parameter modification of monazite baked product to simulate the adsorption of agent OHA on the surface of monazite.