LAUSR

The non-isothermal reduction kinetics and mechanism of iron during vacuum carbothermal reduction of ilmenite concentrate were investigated by X-ray diffraction, backscattered electron imaging, and energy-dispersive X-ray spectroscopy at temperatures from 1273 K to 1673 K (1000 °C to 1400 °C). The pressure dropped and the increasing trend of mass loss and metallization ratios slowed down when the temperature was higher than 1573 K (1300 °C). The reaction products were iron, Ti2O3, and silicate. Iron was mainly obtained by carbothermal reduction of FeTiO3 and FeTi2O5. The irons continued to nucleate, aggregate, and grow during the reduction process. Comprehensive consideration of Šatava–Šesták method and Coats–Redfern method, the apparent activation energy of the reduction process was 587.4 ± 2.98 kJ/mol, and the forms of both integral and differential for the mechanism function were G(a)= [(1−a)−1/3−1]2 and f(a) = 3/2(1−a)4/3[(1−a)−1/3−1]−1, respectively.