Flotation Separation of Spodumene from Feldspar with Combined Collectors: Experimental and Molecular Dynamics...

This work addresses the limitations of traditional sodium oleate (NaOL) collector in spodumene flotation, such as poor flotation performance and high reagent consumption, by introducing 8-hydroxyquinoline (8-HQ) to form a combined collector system. Under the condition of a combined collector dosage of 8 × 10^-4 mol/L and a NaOL to 8-HQ ratio of 4:1, the recoveries of spodumene and feldspar in the single-mineral flotation tests were 81.58% and 12.15%, respectively, achieving effective separation of the two minerals. Furthermore, multiple analytical techniques demonstrated that the higher concentration of Al sites likely provided the fundamental basis for the effective collection of spodumene by the collector. The adsorption mechanism of 8-HQ involved the formation of metal chelates with Al sites on the mineral surface, thereby enhancing its surface activity. The presence of these metal chelates significantly increased the adsorption capacity of NaOL on the mineral surface. Results from molecular dynamics simulations and contact angle measurements indicated that in the combined collector system, both the collector concentration and contact angle on the feldspar surface remain relatively low. In contrast, the collector exhibited stronger adsorption on the spodumene surface, leading to a significant enhancement in surface hydrophobicity compared to the single NaOL system.