An Insight into the Pre-reduction Mechanism of Manganese Ores Using Elemental Sulfur for Ferromanganese Production

The pre-reduction of manganese ore using elemental sulfur under an inert atmosphere at temperatures above 600 °C is required for maximum MnO formation. Under atmospheric conditions, SO 2 formation via sulfur oxidation leads to MnSO 4 , which again will dissociate to lower Mn oxides. Thus, excess energy is required for this conversion, thereby decreasing the overall energy efficiency. The optimum pre-reduction condition obtained is 800 °C, with a holding time of 4 hours at 0.5 S/Mn ratio.