Removal of iron from titanium ore by selective chlorination using TiCl4 under high oxygen chemical potential

•98% TiO2 was produced from low-grade Ti ore using TiCl4 at 1200 K under high pO2.•Iron in the low-grade Ti ore was selectively removed as iron chlorides in a dry form.•Chemical potential region for selective chlorination under high pO2 was analyzed.

With the purpose of developing a new technology for producing high-grade titanium dioxide (TiO2), a fundamental study on the selective chlorination of low-grade titanium ore under a high oxygen chemical potential was carried out. The use of titanium tetrachloride (TiCl4) as a chlorinating agent allowed iron to be directly removed from various types of Ti ores. In the experiments, titanium ore was first pre-oxidized under air, and then reacted with TiCl4 gas at 1100 K or 1200 K for 9 h under an Ar + 1 ppm O2, Ar + 1% O2, or Ar + 10% O2 gas flow. The iron in the low-grade Ti ore was selectively removed as iron chlorides (FeClx [x = 2, 3]) in a dry form, and 98% TiO2 was obtained under certain conditions. This demonstrated that the selective chlorination of low-grade titanium ore by TiCl4 under a high oxygen chemical potential is a feasible method of producing high-grade TiO2 directly.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide