Non-isothermal reduction kinetics of roasted high alumina iron ore pellets

Non-isothermal reduction of roasted Guangxi high alumina iron ore pellets with CO and H₂ was conducted with NETZSCH STA 409C/CD. Non-isothermal kinetics analysis was carried out and kinetics data were obtained. Compared with the possible common mechanisms function in solid state reaction about the correlation coefficient(r), the optimal equations for CO reduction and H₂ reduction were determined. Furthermore, the Arrhenius plots for CO and H₂ reduction were clarified when the kinetic mechanism functions were determined. The results show that the activation energy values of CO and H₂ reduction are 295.82 kJ.mol^-1, and 185.42 kJ.mol^-1, respectively. Obviously, when the temperature is higher than 1357 K, the level of the reaction rate constant of H₂ reduction higher than that of CO reduction increases sharply, that is the capacity of H₂ reduction is better than that of CO reduction in certain conditions. (authors)