Ze-hong Wang, Guo-feng Li, Yong-sheng Sun, and Ming-zhao He, Reduction behavior of hematite in the presence of coke, Int. J. Miner. Metall. Mater., 23(2016), No. 11, pp. 1244-1251. https://doi.org/10.1007/s12613-016-1345-6
Cite this article as:
Ze-hong Wang, Guo-feng Li, Yong-sheng Sun, and Ming-zhao He, Reduction behavior of hematite in the presence of coke, Int. J. Miner. Metall. Mater., 23(2016), No. 11, pp. 1244-1251. https://doi.org/10.1007/s12613-016-1345-6
Ze-hong Wang, Guo-feng Li, Yong-sheng Sun, and Ming-zhao He, Reduction behavior of hematite in the presence of coke, Int. J. Miner. Metall. Mater., 23(2016), No. 11, pp. 1244-1251. https://doi.org/10.1007/s12613-016-1345-6
Citation:
Ze-hong Wang, Guo-feng Li, Yong-sheng Sun, and Ming-zhao He, Reduction behavior of hematite in the presence of coke, Int. J. Miner. Metall. Mater., 23(2016), No. 11, pp. 1244-1251. https://doi.org/10.1007/s12613-016-1345-6
The reduction kinetics of hematite in the presence of coke as a reductant was studied via isothermal and non-isothermal thermodynamic analyses. The isothermal reduction of hematite was conducted at a pre-determined temperature ranging from 1423 to 1573 K. The results indicated that a higher reduction temperature led to an increased reduction degree and an increased reduction rate. The non-isothermal reduction of hematite was carried out from room temperature to 1573 K at various heating rates from 5 to 15 K·min-1. A greater heating rate gave a greater reduction rate but decreased reduction degree. With an increase in temperature, both the reduction rate and the reduction degree increased at a smaller rate when the temperature was less than 1150 K, and they increased at a higher rate when the temperature was greater than 1150 K before completion of the reduction reaction. Both the isothermal and the non-isothermal reduction behaviors of hematite were described by the Avrami–Erofeev model. For the isothermal reduction, the apparent activation energy and pre-exponential factor were 171.25 kJ·mol-1 and 1.80×105 min-1, respectively. In the case of non-isothermal reduction, however, the apparent activation energy and pre-exponential factor were correlated with the heating rate.
The reduction kinetics of hematite in the presence of coke as a reductant was studied via isothermal and non-isothermal thermodynamic analyses. The isothermal reduction of hematite was conducted at a pre-determined temperature ranging from 1423 to 1573 K. The results indicated that a higher reduction temperature led to an increased reduction degree and an increased reduction rate. The non-isothermal reduction of hematite was carried out from room temperature to 1573 K at various heating rates from 5 to 15 K·min-1. A greater heating rate gave a greater reduction rate but decreased reduction degree. With an increase in temperature, both the reduction rate and the reduction degree increased at a smaller rate when the temperature was less than 1150 K, and they increased at a higher rate when the temperature was greater than 1150 K before completion of the reduction reaction. Both the isothermal and the non-isothermal reduction behaviors of hematite were described by the Avrami–Erofeev model. For the isothermal reduction, the apparent activation energy and pre-exponential factor were 171.25 kJ·mol-1 and 1.80×105 min-1, respectively. In the case of non-isothermal reduction, however, the apparent activation energy and pre-exponential factor were correlated with the heating rate.