LAUSR

Abstract In the present work, the flotation separation of magnesite from dolomite was enhanced using sodium dihydrogen phosphate (SDP) as an activator for dolomite and dodecylamine (DDA) as a collector. Based on the findings of micro-flotation examinations, SDP possessed selective-activation effects on the dolomite flotation; however, it had no such effect on the magnesite flotation. Zeta potential measurements revealed that SDP, with its negatively charged functional group, could selectively reduce the dolomite surface potential, which promoted the adsorption of DDA with cationic functional groups on the dolomite surface, while it only included a slight impact on the magnesite. Fourier transform infrared (FTIR) analysis revealed that SDP could be adsorbed selectively on the dolomite surface. Based on the X-ray photoelectron spectroscopy (XPS) analysis, SDP could selectively improve the adsorption of DDA onto the dolomite surface, and also proved that the SDP adsorption selectively onto dolomite could be related to the selective reaction with Ca. Density functional theory (DFT) calculations indicated that the spontaneous adsorption interaction intensity between magnesite and SDP was considerably weaker than that between SDP and dolomite.