Disclosed is a process/system for the removal of metal chloride impurities from a titanium tetrachloride stream. The metal chloride impurities are removed through contact of the titanium tetrachloride stream with an alumino-silicate material, which can be selected based on certain properties of the alumino-silicate and based on the geometries of the impurity(ies) and the alumino-silicate.

The present invention provides a process for recovering transition metal tetrahalides from a waste stream coming from a catalyst manufacturing process by (a) establishing a mixed stream comprising transition metal tetrahalide and transition metal alkoxyhalides; (b) forming a falling liquid film from the mixed stream of step (a) at a temperature of from 25 to 85° C. and an absolute pressure of from 0.05 to 0.6 bar; and (c) establishing from the film of step (b) a first vapour stream containing from 90 to 100% of recoverable components and a second liquid stream containing about 10 to 80% of titanium haloalkoxides.

The present invention provides a process for recovering transition metal tetrahalides from a waste stream coming from a catalyst manufacturing process by (a) establishing a mixed stream comprising transition metal tetrahalide and transition metal alkoxyhalides; (b) forming a falling liquid film from the mixed stream of step (a) at a temperature of from 25 to 85 C. and an absolute pressure of from 0.05 to 0.6 bar; and (c) establishing from the film of step (b) a first vapour stream containing from 90 to 100% of recoverable components and a second liquid stream containing about 10 to 80% of titanium haloalkoxides.

The present invention provides a process for recovering transition metal tetrahalides from a waste stream coming from a catalyst manufacturing process by (a) establishing a mixed stream comprising transition metal tetrahalide and transition metal alkoxyhalides; (b) forming a falling liquid film from the mixed stream of step (a) at a temperature of from 25 to 85 C. and an absolute pressure of from 0.05 to 0.6 bar; and (c) establishing from the film of step (b) a first vapor stream containing from 90 to 100% of recoverable components and a second liquid stream containing about 10 to 80% of titanium haloalkoxides.

A method for separating one or more titanium (halo) alkoxides from a liquid mixture comprising titanium tetrachloride TiCl.sub.4 and at least one titanium (halo) alkoxide, said method comprising: agitating and cooling the liquid mixture until crystallization of at least one titanium (halo) alkoxide occurs in the liquid mixture; separating the crystallized titanium (halo) alkoxide from the mixture; and optionally, washing the separated, crystallized titanium (halo) alkoxide with a solvent.

The invention relates to a method for separating valuable metal chlorides, particularly titanium tetrachloride and niobium pentachloride, from solid residues, in particular the filter dust generated during the chlorination of raw materials containing iron and titanium in the production of titanium dioxide using the chloride process.

A method for producing titanium tetrachloride is provided, in which valuable materials such as unreacted titanium-containing raw material, carbon raw material and chlorine can be recovered from solid recovered material generated in chlorinating process of titanium-containing raw material, and titanium-containing raw material can be efficiently used. The treatment method of titanium-containing raw material includes the steps: separating and removing impurities selectively from the titanium-containing raw material as chlorides so as to obtain high titanium-containing raw material, producing titanium tetrachloride using the high titanium-containing raw material, and performing separating process of impurities from solid recovered material byproduced in the production of titanium tetrachloride, together with selective chlorinating treatment of the titanium-containing raw material. Thus, the high titanium-containing raw material can be produced while recovering chlorine and impure oxides.

The invention relates to a method for recycling chlorine in the production of titanium tetrachloride. Further, the invention refers to the use of this method in the chloride process to produce titanium dioxide.