Utilization of a novel "crab"-shaped collector with dicarboxyl groups for targeted flotation of fluorite

The core of mineral flotation resides in specific matching between collectors and mineral surfaces. Amid new energy-driven fluorite demand, efficiently separating it from similarly interfaced calcite remains challenging due to non-selective fatty acid collectors. Herein, a novel "crab"-shaped dicarboxylic collector, N-Benzyloxycarbonyl-glutamic acid (ZGA), was synthesized and its flotation performance was evaluated. Single-mineral flotation showed that at a concentration of 2 × 10 −5 mol/L and pH 9, the recovery difference between fluorite and calcite reaches 56.96 %, while the synergistic enhancement of terpineol further boosts fluorite recovery to over 90 %. Surface characterizations confirmed that ZGA undergoes selective adsorption via chemical and electrostatic interactions, which effectively modifies the surface roughness of fluorite and significantly enhances its hydrophobicity. DFT calculations demonstrated the dicarboxylic distance matches alternating Ca 2+ on fluorite (111), enabling stable adsorption with an adsorption energy of −325.256 kJ/mol. Flotation practice yielded improved metrics, with the CaF 2 concentrate grade reaching 96.45 % and recovery increasing by 2.76 %. These findings offer valuable insights for the design of collector selective to fluorite, while facilitating the efficient and clean separation of strategic calcium-containing minerals.