Abstract: The effect of dissolved chlorine（Cl₂） in crude titanium tetrachloride（TiCl₄） on the product quality and vanadium removal process by aluminum powder was studied using the industrial devices of a titanium sponge plant as test platform.The results show that the content of dissolved Cl₂ in crude TiCl₄ has an important influence on the product quality and vanadium removal process. With the dissolved Cl₂ increased both the consumption of titanium trichloride（TiCl₃） slurry and pressure of the tower top increase.In addition,the content of vanadium oxytrichloride（VOCl₃） in product also increases（during the industrial production process,dissolved Cl₂ in TiCl₄ should be less than 0.15%）.Thus,the excess coefficient of Cl₂ for industrial chlorination process should be controlled to decrease the dissolved Cl₂ content of crude TiCl₄.For the crude TiCl₄ with high content of Cl₂,pre-distillation operation should be adopted to reduce the Cl₂ content to 0.15% or less,and then the vanadium removal can be operated.