Which process of purification is represented by the following equation? TiImpure+2I2→250∘ CTiI4→1400∘ CTipure+2I2

Van Arkel process:Titanium metal is purified by this method. When the impure titanium metal is heated with iodine at a temperature of  250∘ C, volatile titanium tetra-iodide is formed TiI4. The impurities are left behind, as they do not react with iodine.The titanium tetra-iodide vapour is passed over a hot tungsten filament at 1400∘ C. The vapour is decomposed and pure titanium is deposited on the filament and is removed. The iodide reused.