The application of a novel amine collector, 1-(dodecylamino)-2-propanol, in the reverse flotation separation of apatite and quartz

Abstract

This study synthesized a novel amine collector, 1-(dodecylamino)-2-propanol (DDAIP), by incorporating a 2-hydroxy propyl group into the molecular structure of dodecylamine (DDA). Flotation experiments showed that utilizing DDAIP collector resulted in a substantial difference of ∼80% in flotation recoveries between apatite and quartz. Employing DDA as the collector yielded a difference of ∼30% in flotation recoveries between the two minerals. DDAIP demonstrated a superior selectivity in the reverse flotation separation of apatite and quartz in comparison to DDA. Zeta potential experiments indicated that, under identical dosages, DDAIP demonstrated increased adsorption capacities on quartz surface in contrast to DDA, whereas the adsorption amounts on apatite surface remained similar for both the collectors. By combining XPS analysis and first-principles calculations, DDAIP demonstrated enhanced chemical interactions with the Si atoms on quartz surface and a greater number of hydrogen bonds with quartz surface compared to DDA. The presence of an isopropyl group between the hydroxyl and secondary amine groups in DDAIP molecular structure leads to steric hindrance, hindering the simultaneous chemical interactions of the O and N atoms in DDAIP with the Ca2+ ions on apatite surface. Thus, the incorporation of the 2-hydroxy propyl group into DDAIP molecular structure does not enhance its adsorption strength on apatite surface when compared to DDA.