Smithsonite flotation with lauryl phosphate

Abstract

Smithsonite, the most abundant nonsulfide zinc mineral, has attracted growing attention due to the demand for zinc and the exhaustion of traditional sulfide zinc resources. Traditional flotation techniques are not efficient and do not easily separate smithsonite from other carbonate minerals, such as calcite. In this regard, lauryl phosphate was evaluated as a flotation collector with respect to physicochemical aspects, which include surface charge, wettability, and flotation performance by the examination of contact angle, zeta potential, sum frequency generation spectroscopy (SFG), and flotation experimental results, as well as interaction energy calculations. The contact angle, zeta potential, and SFG results indicate that lauryl phosphate prefers to adsorb at the smithsonite surface when compared to calcite. The microflotation and interaction energy results further confirmed that an obvious flotation difference was observed between smithsonite and calcite, using lauryl phosphate between pH 5 and pH 9. However, the use of the typical collector, dodecylamine, results in no significant difference between smithsonite and calcite flotation recovery as a function of pH. These findings provide a comprehensive evaluation of the potential of lauryl phosphate as an effective collector in recovering smithsonite from oxide zinc ores.