Investigate the oxidation induration mechanism of manganese-bearing magnetite concentrate pellets

In this study, to promote the application of manganese-containing magnetite, the oxidation induration mechanism for manganese-bearing magnetite concentrate pellets (MBMCP) was investigated. X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy, and thermogravimetric analyses were carried out to systematically study the phase composition, microstructure, elemental distribution, and oxidation behaviour of the MBMCP. The results indicated that Mn3O4 exerted had a negative effect on the oxidation induration of the pellet. With an increase in the amount of added Mn3O4, the compressive strength and oxidation degree significantly decreased and the porosity increased. The content of the formed Mn-Fe solid solution (MnFe2O4) increased with the increase of Mn3O4, which made the matrix of the MBMCP change from dense to porous, suggesting that the growth of haematite grains was inhibited and the bridging between haematite grains was broken. These results provide the theoretical and technical foundations for the industrial production of MBMCP.