Depression effect of acid surface pretreatment on the flotation behaviors of four classified titanaugites

Abstract

• Four titanaugites had different recoveries with the maximums from 15% to 80%. • Acid surface pretreatment lowered their flotation recoveries to around zero. • Acid surface pretreatment made the negative shifts of zeta potentials . • The main active sites were undiscovered after acid surface pretreatment. • Acid surface pretreatment decreased NaOL adsorption and surface hydrophobicity . The effect of acid surface pretreatment on the flotation behaviors of four classified titanaugites was investigated with NaOL collector. The floatability of four titanaugites increased with the increase of NaOL concentration, and their range of the highest recoveries from 15% to 80%. After acid surface pretreatment, their flotation recoveries were all reduced to around zero. The acid surface pretreatment decreased the NaOL adsorption and surface hydrophobicity of four titanaugites. The results of XPS and AFM analyses indicated that when treated with acid surface pretreatment, the surface morphologies of four titanaugites appeared the irregular fluid and scour shapes, and the Fe, Ca, and Mg active sites for NaOL adsorption were undetected. Thus, NaOL collector was difficult to adsorb onto new generated surfaces of these four titanaugites, lowering their floatability. The acid surface pretreatment could eliminate the effect of the diversity of titanaugites in the flotation of ilmenite ore.