Effect of temperature on magnetizing reduction of agbaja iron ore

Agbaja oolitic iron ore, which has not been responsive to such beneficiation processes as froth flotation, gravity concentration, magnetic separation, and electrostatic separation, has been concentrated to 60 pct Fe grade and 87.3 pet Fe recovery (starting from a crude assaying 45.6 pct Fe) by the magnetizing reduction technique. The main parameter investigated was the effect of temperature on the magnetizing reduction process, and 600 °C was established as the optimum temperature for the reduction step. X-ray diffraction studies of the reduction products showed that the iron oxides were converted to magnetite, to wustite, or to metallic iron, depending on the temperature of reduction. The results from the subsequent magnetic concentration step were, in the main, dependent on the observed reduction products.