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 technique is provided in which valuable material is recovered from solid recovered material generated during chlorinating process of titanium-containing raw material, and in particular, in which chlorine gas and titanium-containing raw material can be efficiently separated and recovered from the solid recovered material. The method for production of titanium tetrachloride includes: a chlorinating process in which titanium-containing raw material, coke and chlorine are reacted, a recovering process in which chlorine gas, titanium oxide and coke are recovered by treating solid recovered material which is byproduced during the chlorinating process, and a reusing process in which these recovered material are reused as raw material for the chlorinating process.

A metal-containing film can be formed with high continuity with respect to a base when forming the metal-containing film on the base by CVD or ALD. A film forming method of forming, by ALD or CVD, a Ti-containing film on a base film of a processing target object having a SiO.sub.2 film as the base film includes performing a surface processing of accelerating formation of a silanol group on a surface of the SiO.sub.2 film by bringing a fluid containing O and H into contact with the surface of the SiO.sub.2 film; and performing a film forming processing of forming the Ti-containing film on the SiO.sub.2 film, on which the surface processing is performed, by the ALD or the CVD with a Ti source gas which reacts with the silanol group.

This disclosure relates to a fluidized bed reaction system and method for continuous production of titanium tetrachloride from titanium-bearing materials containing high concentrations of alkaline earth metal impurities. Agglomerated heavy particles in a reaction are taken out continuously from a chlorination reactor without clogging and stopping. The reactors and related methods disclosed apply to the chlorination of titanium slag containing high content of alkaline earth metal oxides of up to 15% by weight.

This disclosure relates to an improved method to produce titanium tetrachloride continuously from titanium-bearing materials containing high concentrations of alkaline earth metal impurities through fluidized-bed carbochlorination. Agglomerated heavy particles in a reaction are taken out continuously from a chlorination reactor without clogging and stopping. The reactors and related methods disclosed apply to the chlorination of titanium slag containing high content of alkaline earth metal oxides of up to 15% by weight.

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.

There are provided processes for treating red mud. For example, the processes can comprise leaching red mud with HCl so as to obtain a leachate comprising ions of a first metal (for example aluminum) and a solid, and separating said solid from said leachate. Several other metals can be extracted from the leachate (Fe, Ni, Co, Mg, rare earth elements, rare metals, etc.). Various other components can be extracted from solid such as TiO.sub.2, SiO.sub.2 etc.