Flotation routes for a phosphate ore bearing silicate-carbonate gangue.

Abstract

This laboratory scale investigation addressed two different process routes for the concentration of a phosphate ore bearing a silicate-carbonate gangue: (i) bulk apatite and calcite flotation followed by calcite flotation in the presence of phosphoric and citric acids; (ii) calcite flotation in the presence of carbon dioxide followed by apatite flotation. The target of selectively separating apatite from the contaminating silicates and carbonates was achieved. Following the flotation experiments, calcite zeta potential determinations were performed aiming at clarifying the mechanisms that rule the adsorption of the soybean bran oil soap onto the mineral surface in the presence of the modifying agents phosphoric acid, citric acid, and carbon dioxide.