Enhanced flotation separation of ilmenite from titanaugite by novel N-hydroxy-3-(4-methoxyphenyl) acrylamide collector

To improve the separation of ilmenite from its associated gangue mineral titanaugite through selective flotation, a novel hydroxamic acid derivative, N-hydroxy-3-(4-methoxyphenyl) acrylamide (HMPA), was successfully synthesized and evaluated as an efficient collector. Comparative flotation tests demonstrated that HMPA outperformed conventional sodium oleate, achieving superior separation efficiency with a TiO₂ concentrate grade of 48.95 % and an impressive recovery rate of 76.0 %. To understand the underlying mechanisms, the interactions between HMPA and the mineral surfaces were investigated meticulously by adsorption capacity tests, contact angle analysis, FTIR, and XPS. The results of contact angle and adsorption measurements intuitively revealed that HMPA exhibited significantly greater adsorption capacity on the ilmenite surface compared to titanaugite. FTIR and XPS analyses indicated that HMPA adsorbed strongly onto the ilmenite surface through chelation with reactive Ti and Fe sites. Density functional theory (DFT) calculations further suggested that HMPA could act as a bidentate ligand, forming a stable five-membered chelate structure through interactions with the Ti and Fe active sites on the ilmenite surface. In conclusion, HMPA demonstrated outstanding collecting ability and selectivity, making it a highly promising collector for ilmenite flotation.