The application and mechanism of degradable activator biologically small molecule organic acids in smithsonite flotation

Utilizing an efficient activator is an efficient solution to overcome the low recovery flotation of zinc oxide ore. We proposed amino acids as new high-efficiency biological activators for zinc oxide ore flotation and systematically studied the effects of amino acids as activators in the flotation of zinc oxide ore. Fourier transform Infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and density functional theory (DFT) calculations were conducted to reveal the activation mechanism of amino acids in smithsonite flotation. The results showed that tryptophan (Trp) significantly promoted the floatability of smithsonite by coordinating with zinc sites on the surface of smithsonite. The addition of Trp broke the Zn-O bonds in the crystal and exposed more highly active Zn on the crystal surface, which easily reacted with sodium oleate. At the same time, Trp increased the concentration of Zn2+ in the pulp, and an appropriate amount of Zn2+ in the solution owned a certain activation effect, which finally improved the adsorption of NaOL on the surface of smithsonite. DFT showed that Trp interacted strongly with smithsonite, and the carboxyl O atom of Trp coordinated with Zn on the surface of smithsonite.