Preparation of cinnamic hydroxamic acid collector and study on flotation characteristics and mechanism of scheelite

In this paper, using methyl cinnamate as raw material, the new cinnamic hydroxamic acid collector (CIHA) was synthesized by the hydroxylamine method. The collector performance of hydroxamic acid was investigated for scheelite and gangue calcite, and the flotation separation test of scheelite and calcite was carried out with CIHA as the collector. The interaction mechanism between hydroxamic acid and scheelite minerals has also been investigated through zeta potential, Fourier transform infrared spectroscopy (FTIR) experiments, X-ray photoelectron spectroscopy (XPS) experiments, and density functional theory (DFT) calculation. The single mineral flotation test and artificially mixed ore showed that CIHA had an excellent collection effect and selectivity. Zeta potential, FTIR, and XPS showed that CIHA was adsorbed on the scheelite surface by strong chemical adsorption. The active group of CIHA was analyzed through quantum chemical calculation. It was speculated that CO and NO bonds could synthesize a five-membered chelated hydroxamic acid group with Ca element chelate on scheelite surface, changing hydrophobicity and making it more likely to emerge from the pulp.