Effect of TiO2 on reduction behavior of Cr2O3 in CaO–SiO2–Al2O3–MgO–TiO2–Cr2O3 by carbon from Fe–C melt

Abstract

The chromium-bearing titanomagnetite ore will turn to be the important raw material for blast furnace process in Panxi area, China. The reduction behavior of Cr2O3 between CaO–SiO2–Al2O3–TiO2–Cr2O3 and Fe–C systems was investigated. The effect of TiO2 content in the slag system on the reduction of Cr2O3, TiO2, and SiO2 and the consumption of C in hot metal was investigated by both theoretical calculation and physical experiment. The theoretical calculation results reveal that higher reduction temperature promotes the reduction of Cr and Ti, while high basicity and TiO2 content have little influence on the reduction of chromium but significantly influence the reduction of Ti. The smelting reduction experiment results show that the content of Cr in hot metal significantly increases with extending the reduction time and decreases with the increase in TiO2 content. However, the content of Ti in hot metal significantly increases as the TiO2 increases, reaching 0.073, 0.085, 0.107, and 0.121 wt.% for 5, 10, 15, and 20 wt.% of TiO2 input, respectively. Kinetic studies proved that the reduction of Cr2O3 was a first-order reaction. The addition of TiO2 inhibited the reduction of Cr2O3 and resulted in the decrease in reaction rate constant.