Development of a Novel Titania Slag Upgrading Process Using Titanium Tetrachloride

In order to remove iron from titania slag for the production of high-grade titanium dioxide (TiO₂), a novel slag upgrading process was developed based on a selective chlorination method. In the experiments, various types of suitably pretreated slag reacted with titanium tetrachloride (TiCl₄) as a chlorinating agent at 1100 K (827 °C) for 5 hours in the presence of carbon. Once the reaction had reached completion, the iron in the slags was selectively removed as iron chloride (FeCl₂) in a dry form. As a result, the mass percent of iron decreased from 13.9 to 0.21 pct (nominal, excluding oxygen) and the mass percent of titanium increased from 78.1 to 96.0 pct (nominal, excluding oxygen) under certain conditions. Therefore, this selective chlorination process using TiCl₄ is considered a feasible approach for the upgrading of titania slag.