Which method is used for refining Zr

Van Arkel method is used for refining Zr and Ti. Van Arkel process involves heating the impure metal with Iodine. It forms a volatile complex which on decomposition at high temperatures, gives back the metal but in very pure form.

Refining of Zr and Ti using Van Arkel method

For Zirconium,

Zr(impure) + 2I2→ ZrI4

ZrI4→Zr(pure) + 2I2 (at 1800K)

For Titanium,

Ti(impure) + 2I2→ TiI4

TiI4 → Ti(pure) + 2I2 (at 1800K)