Reduction of manganese ores - A comparative study

The reducibility of three different manganese ores with coke was studied at low temperatures. The three ores exhibited different reducibility behaviour. From the data obtained, it could be inferred that in the temperature range studied (900–1000°C), Fe₂O₃ was reduced to metallic iron. MnO₂ was reduced to Mn₃O₄ in all cases except one in which it was reduced to Mn₂O₃. The kinetics of reduction was controlled by diffusion in the last case. It was controlled either by chemical reaction or nucleation in the other cases. The relative reducibility of the ors changed with temperature.