Adsorption study of potential collector polyoxyethylene ether phosphate on magnesite

The anionic-nonionic surfactant polyoxyethylene ether phosphate exhibits several advantages, as the surfactant is a potential collector for magnesite flotation, is easy to prepare and exhibits high surface activity. In this work, the flotation performance of fatty alcohol polyoxyethylene ether phosphate (AEOP) on magnesite was investigated and compared with that of dodecyl phosphonic (DP) and dodecyl phosphonate (DOP), and the results show that AEOP can be used at lower concentrations and a wider range of pH values. Zeta potential tests, Fourier transform infrared spectroscopy tests, and X-ray photoelectron spectroscopy tests demonstrated that AEOP was chemisorbed on the surface of magnesite by acting on the Mg sites. DFT calculations further demonstrated that both AEOP−1 and AEOP−2 were adsorbed on magnesite surfaces via mononuclear monodentate and binuclear bidentate configurations, which were similar to DP and DOP. In addition, the nonionic EO groups were not involved in the adsorption process.