| As a fundamental research to establish an efficient process for the solid-state reduction of chromite, reduction behavior of natural chromites were investigated experimentally and interpreted in terms of thermodynamics. The results obtained were as follows; 1) The reduction of oxide components in natural chromite tended to process in the sequence of Fe₃O₄, FeCr₂O₄ and MgCr₂O₄. The tendency was pronounced at low temperatures. 2) Below 1200℃, reduction of chromite proceeded sequentially, i.e. (Mg, Fe)(Cr, Al, Fe)₂O₄→ Fe or Fe₃C+Fe-poor Non-stoichimetric chromite → (Fe, Cr)_7C₃+MgAl₂O₄ 3) Above 1200℃, reduction of chromite proceeded sequentially, i.e. (Mg, Fe)(Cr, Al, Fe)₂O₄ → (Fe, Cr)_7C₃+Non-stoichimetric chromite → (Fe, Cr)_7C₃+MgAl₂O₄ 4) Reduction degree of chromite was higher with increasing Fe/Cr ratio of chromite composition. 5) Reduction rate of various chromite ore by solid carbon is higher in order SA, RM, IH, PH and IM at the same condition. |
|
