Selective co-adsorption mechanism of a new mixed collector on the flotation separation of lepidolite from quartz

Abstract

In this study, the floatability of lepidolite and quartz under the reaction of single collector SOL or dodecylamine (DDA) and mixed collector SOL/DDA was studied by micro-flotation experiments. The actual flotation separation effect of the two minerals under the conditions of mixed collector and single collector was studied by artificial mixed minerals experiment. The co-adsorption and the selective adsorption mechanism of the mixed collector were revealed by contact angle experiments, zeta potential experiments, adsorption amount measurement. The adsorption morphology of the flotation reagents on mineral surface was detected by atomic force microscope (AFM). The micro-flotation experiments show that the selective separation of lepidolite and quartz could not be achieved under the condition of single collector under neutral pH conditions, but the flotation separation of two minerals could be achieved using the mixed collector at around pH 7.0. The artificial mixed minerals experiments prove the excellent flotation separation effect of the two minerals under the condition of mixed collector at pH 7.0. The contact angle experiments show that the contact angle of lepidolite was much larger than quartz under the condition of combined collector. The zeta potential experiments show that the mixed collectors had stronger co-adsorption on the surface of lepidolite than quartz. The adsorption experiments show that the anionic collector SOL in the mixed collector hindered the adsorption of DDA on the surface of quartz, but did not affect the adsorption on the surface of lepidolite. AFM observes that the combined collectors showed point-like and layered adsorption on the surface of lepidolite, demonstrating the co-adsorption of the combined collectors on the mineral surface.