Kinetics Study on Solid-phase Catalytic Reduction of Highly Impure Ilmenite by Thermal Analysis

In order to reduce the highly impure ilmenite by carbon at solid phase,the mechanism of the catalytic reduction of ilmenite by thermogravimetric analysis has been studied. The results show that impurities hinder the process of ilmenite reduction. Low reduction rate occurs during the catalyst-free reduction process while a higher reduction rate and a faster reduction velocity can be achieved by adding a small amount of catalyst. The different anionic groups of catalysts have different effects on the reaction. In the case of the same molar concentration of sodium ion,the catalyst having the best catalytic effect is Na₂B₄O₇,successively followed by NaF,NaCl and Na₂SiO₃. In the temperature range of 860~1 100℃,the main rate-controlling step for ilmenite reduction is the interfacial chemical reaction. The apparent activation energy of the catalyst-free reaction is 260.976 kJ/mol; the reduction adding the catalyst of Na₂B₄O₇ has the lowest apparent activation energy of 226.182 kJ/mol.