text: is produced by the chloride process, which involves the reduction of titanium oxide ores, typically ilmenite (), with carbon under flowing chlorine at 900 °C. Impurities are removed by distillation.
  The coproduction of Iron(III) chloride| is undesirable, which has motivated the development of alternative technologies. Instead of directly using ilmenite, "rutile slag" is used. This material, an impure form of , is derived from ilmenite by removal of iron, either using carbon reduction or extraction with sulfuric acid. Crude  contains a variety of other volatile halides, including vanadyl chloride (), silicon tetrachloride (), and tin tetrachloride (), which must be separated.