Enhancement of the low temperature chlorination of ilmenite with CCl4 by adding Cl2

This work reports a simple and effective way to enhance the chlorination of natural ilmenite with carbon tetrachloride (CCl4) at low temperature by using chlorine gas (Cl2). The phase transition of ilmenite during chlorination was characterized by X-ray diffraction (XRD) method and transmission electron microscopy (TEM). It is found that CCl4 and Cl2 can act as the oxidant to convert ilmenite to M5O9 and M13O23 intermediate compounds which are members of a M3O5–M2O4 intergrowth structure series, and then further chlorinate it to produce titanium tetrachloride (TiCl4). The solid phase transition from ilmenite to the intermediate phases was the rate controlling step. Cl2 can significantly enhance this process by promoting the formation of the intermediate phases. The enhanced process can be commercially exploited as an environmental protection technology to produce TiCl4 at low temperature.