Effect of siderite dissolution on mineral particles interaction in aqueous suspension

Abstract Siderite dissolution and its effects on the interaction between siderite and quartz particle was investigated through focused beam reflectance measurement (FBRM) particle size analysis (a real-time particle characterization tool), zeta potential distribution measurement, and DLVO theoretical calculations, supplemented by dissolution tests, solution chemistry calculation, and X-ray photoelectron spectroscopy (XPS) analysis. The results of FBRM and zeta potential distribution measurement showed that the hetero-aggregation scarcely formed in the siderite-quartz mixture system, which was contrary with the calculated attraction energies (VTD) between siderite and quartz at pH 5.0. Dissolution test and solution chemistry calculation indicated that siderite could dissolve lattice ions, beside compression effects on the double electrode layer, the dissolved ferrous ions can also adsorb onto the negatively charged surface of quartz, which was confirmed by the results of zeta potential and XPS analysis. These would weaken the electrostatic attraction energies (VE) between siderite and quartz at pH 5.0, resulting in depressing the hetero-aggregation.