An Investigation into the Effects of Grinding Media on Grinding Products Characteristics and Flotation Performance of Pyrite

During the grinding of pyrite, the grinding medium affects the properties of the grinding products, which in turn affects its flotation performance. In this study, we investigated the effects of cast iron ball (CIB) and ceramic ball (CB) grinding media on the grinding products characteristics and flotation performance of pyrite using atomic absorption spectrometry, scanning electron microscopy combined with energy dispersive spectrometry, X-ray photoelectron spectroscopy, contact angle measurement, and single mineral flotation analysis. The results showed that the Fe(3+)and SO(4)(2-)concentrations and pH value of the pulp were significantly lower in the case of grinding with the CB medium than with the CIB medium, whereas the dissolved oxygen content of the pulp was significantly higher. The surfaces of the pyrite samples produced by the CB grinding medium were relatively even and smooth with a small amount of formation and coverage of FeOOH as compared to those of the pyrite samples produced by the CIB grinding medium, resulting in a superior hydrophobicity and floatability. Resultantly, the pyrite samples obtained using the CB grinding medium exhibited better performance in flotation recovery than those obtained using the CIB grinding medium. The presence of ferric ions was adverse to pyrite flotation because of the formation of ferric hydroxyl complex. CB shows great potential to be used as grinding medium for pyrite.