Chloride process

The Chloride process is used to purify titanium dioxide from minerals containing at least 90% titanium dioxide. In this process, the feedstock is heated at 900 °C with carbon and chlorine gas, giving titanium tetrachloride. Other impurities are converted to the respective chlorides as well. The titanium tetrachloride is purified by distillation, and oxidized with oxygen to give the pure TiO2.

The Kroll process is a related technique. Instead of oxidizing the distilled titanium tetrachloride with oxygen, it is reduced with magnesium to give titanium metal.