Effect of various states of Fe on the reduction of Cr₂O₃

The effect of various states of Fe(Fe,FeO,and Fe₂O₃) on the reduction of Cr₂O₃ was investigated by conducting isothermal experiments on the reduction of Fe-Cr₂O₃,Fe₂O₃-Cr₂O₃ and FeCr₂O₄ by graphite at 1350-1550℃ combined with X-ray diffraction and scanning electron microscopy with energy-dispersive spectrometry. It is shown that the tendency of final reduction degree is Fe₂O₃-Cr₂O₃-C 〉 FeCr₂O₄-C 〉 Fe-Cr₂O₃-C at each temperature,and the transformation path of the three samples is oxides → carbides → Fe-Cr-C alloy. Liquid alloy which earlier emerges and low carbon-content carbides promote the reduction of Fe₂O₃-Cr₂O₃. Low carbon dissolution in liquid alloy limits the reduction degree of FeCr₂O₄. The large amount of carbides and little liquid alloy retard the reduction of Fe-Cr₂O₃. The apparent activation energies of Fe-Cr₂O₃-C,FeCr₂O₄-C and Fe₂O₃-Cr₂O₃-C are 142.90,111.84 and 128.9 kJ·mol^-1,respectively.