Utilization of tetrasodium iminodisuccinate to eliminate the adverse effect of serpentine on the flotation of pyrite

Flotation results demonstrated that tetrasodium iminodisuccinate (IDS) could effectively eliminate the adverse effect of serpentine on the flotation of pyrite. Furthermore, the interaction mechanism was systematically investigated through zeta potential measurements, Fourier transform infrared (FTIR) spectroscopy analyses, scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) analyses, inductively coupled plasma optical emission spectroscopy (ICP-OES) tests and X-ray photoelectron spectroscopy (XPS) analyses. Results indicated that IDS could chemically react with Mg sites on serpentine surface and form soluble complex compounds, which accelerated Mg dissolution from serpentine surface and shifted serpentine surface potential. In addition to this mechanism, the adsorption of negatively charged IDS onto serpentine surface was also responsible for the reduction of serpentine surface potential. In this way, the serpentine coating on the surface of pyrite was removed.