Reductive kinetics of Panzhihua ilmenite with hydrogen

The hydrogen reduction of Panzhihua ilmenite concentrate in the temperature range of 900-1050 °C was systematically investigated by thermogravimetric analysis (TG), X-ray diffraction (XRD) and scanning electron microscopy (SEM) methods. It was shown that the products of the Panzhihua ilmenite reduced at 900 °C were metallic iron and rutile. Above 1000 °C, ferrous pseudobrookite solid solution was generated. During the reduction process, element Mg gradually concentrated to form Mg-rich zone which can influence the metallization process. The reduction reaction proceeded topochemically and its related reduction kinetics were also discussed. The kinetics of the reduction indicated that the rate-controlling step was the diffusion process. The apparent activation energy of the hydrogen reduction of Panzhihua ilmenite was calculated to be 117.56 kJ/mol, which was larger than that of synthetic ilmenite under the same reduction condition.