The effects of nucleation and growth on the reduction of Fe2O3 to Fe3O4

The kinetics of reduction of hematite powder to magnetite in CO-CO₂ gas mixtures at temperatures between 500 and 663 °C have been measured. The reactions are described in terms of a simple nucleation and growth model. The chemical reaction rate constants for the reduction of hematite to magnetite are obtained and the nucleation frequencies of magnetite on hematite are calculated for a range of temperatures and oxygen partial pressures. A possible technique for the improvement of the “reducibility” of dense hematite ores is suggested. Formerly at Metallurgy Department, Strathclyde University, Glasgow, Scotland.