Flotation separation of spodumene and albite with activation of calcium ion hydrolysate components

It is difficult to separate spodumene and albite by flotation with calcium ion as activator. In this study, micro-flotation experiment, solution chemistry calculation, density functional theory (DFT) calculation and X-ray photoelectron spectroscopy (XPS) analysis were conducted to investigate the effect mechanism of calcium hydrolysate on the flotation separation of spodumene and albite. Results show that the weak interaction intensity of Ca2+ with O atoms on the mineral surface makes it difficult to activate minerals effectively. The O atom in the hydroxyl group of Ca(OH)+ and Ca(OH)2 can be strongly bonded with Al atom on the mineral surface, which greatly improves the adsorption strength. After the activation of Ca(OH)+, the adsorption forms of collectors on the surface of spodumene and albite are quite different, and the adsorption intensity on the surface of spodumene is higher, which is conducive to the flotation separation of spodumene and albite. After the action of Ca(OH)2, the adsorption of the collector on the albite surface is stronger than that of spodumene, which is not conducive to the flotation separation of the two minerals. By adjusting the initial concentration of calcium ions and pulp pH, Ca(OH)+ is the main active component, which is the key to improve the separation effect of spodumene and albite.Graphical abstract