Titanium -chloride

Precipitation of a hydrated titanium oxide by mixing aqueous solutions of titanium chloride with alkaU forms the precipitation seeds, which are used to initiate precipitation in the Mecklenburg (50) variant of the sulfate process for the production of pigmentary titanium dioxide. Hydrolysis of aqueous solutions of titanium chloride is also used for the preparation of high purity (>99.999%) titanium dioxide for electroceramic appHcations (see Ceramics). In addition, hydrated titanium dioxide is used as a pure starting material for the manufacture of other titanium compounds. 

Manufacture. Titanium chloride is manufactured by the chlorination of titanium compounds (1,134—138). The feedstocks usually used are mineral or synthetic mtile, beneficiated ilmenite, and leucoxenes. Because these are all oxygen-containing, it is necessary to add carbon as well as coke from either coal or fuel oil during chlorination to act as a reducing agent. The reaction is normally carried out as a continuous process in a fluid-bed reactor (139). The bed consists of a mixture of the feedstock and coke. These are fluidized by a stream of chlorine iatroduced at the base (see Fluidization). The amount of heat generated in the chlorination process depends on the relative proportions of CO2 or CO that are formed (eqs. 1 and 2), and the mechanism that... 

These facts would suggest that die electrolysis of molten alkali metal salts could lead to the inuoduction of mobile elecU ons which can diffuse rapidly through a melt, and any chemical reduction process resulting from a high chemical potential of the alkali metal could occur in the body of the melt, rather than being conhned to the cathode volume. This probably explains the failure of attempts to produce tire refractoty elements, such as titanium, by elecU olysis of a molten sodium chloride-titanium chloride melt, in which a metal dust is formed in the bulk of the elecU olyte. 

Titan, n. titanium, -chlorid, n. titanium chloride, esp. the tetrachloride. 

Addition of tetra(isopropoxy)titanium results in a slight increase in yield, but does not lead to an exchange of the cation which can be accomplished with tri(isopropoxy)titanium chloride (Section D.1.3.3.3.8.2.3.). In none of these cases could a trace of a second diastereomer be detected112,113. 

The conclusion may be drawn that the data obtained of comparative studies of olefin polymerization by the one-component catalyst (TiCl2) and two-component systems (TiCl2 + AlEtxCl ) confirm the concept of monometallic active centers on the surface of titanium chlorides developed by Cossee and Arlman (170-173). 

Titanium, tetrakis(trimethysilyl)oxy-, 3, 334 Titanium, tetranitrato-stereochemistry, 1,94 Titanium, triaquabis(oxalato)-structure, I, 78 Titanium, tris(acetylacetone)-structurc, 1,65 Titanium alkoxides oligomeric structure, 2,346 synthesis ammonia, 2, 338 Titanium chloride photographic developer, 6,99 Titanium complexes acetylacetone dinuclear, 2, 372 alkyl... 

Very little is known about chalcogenide halides of Group IVB elements. Although the existence of sulfide chlorides (45, 274, 329, 365) and of a selenide chloride (329) of titanium was claimed in early publications, their true composition, and even their existence, remains doubtful. They have usually been obtained by the reaction of titanium chlorides with sulfur and selenium, respectively, or with hydrogen sulfide. The synthesis of a pure compound, TiSClj, was published in 1959 (113). It is an intermediate of the reaction of TiCU with HjS. 

Treatment of N-benzoyl-L-alanine with oxalyl chloride, followed by methanolic triethylamine, yields methyl 4-methyl-2-phenyloxazole-5-carboxylate 32 <95CC2335>. a-Keto imidoyl chlorides, obtained from acyl chlorides and ethyl isocyanoacetate, cyclise to 5-ethoxyoxazoles by the action of triethylamine (e.g.. Scheme 8) <96SC1149>. The azetidinone 33 is converted into the oxazole 34 when heated with sodium azide and titanium chloride in acetonitrile <95JHC1409>. Another unusual reaction is the cyclisation of compound 35 to the oxazole 36 on sequential treatment with trifluoroacetic anhydride and methanol <95JFC(75)221>. 

As shown in Table IV, the highest catalytic activity of metal halides used as Lewis acid for the alkylation reaction of ferrocene with 2 was observed in methylene chloride solvent. Among Lewis acids such as aluminum chloride, aluminum bromide, and Group 4 transition metal chlorides (TiCl4, ZrCU, HfCU), catalytic efficiency for the alkylation decrea.ses in the following order hafnium chloride > zirconium chloride > aluminum chloride > aluminum bromide. Titanium chloride... 

The metal catalyzed production of polyolefins such as high density polyethylene (HDPE), linear low density polyethylene (LLDPE) and polypropylene (PP) has grown into an enormous industry. Heterogeneous transition metal catalysts are used for the vast majority of PE and all of the PP production. These catalysts fall generally within two broad classes. Most commercial PP is isotactic and is produced with a catalyst based on a combination of titanium chloride and alkylaluminum chlorides. HDPE and LLDPE are produced with either a titanium catalyst or one based on chromium supported on silica. Most commercial titanium-based PE catalysts are supported on MgCl2. 

A third class of catalysts was prepared by electron beam induced deposition of XiCl4 on a polycrystalhne Au foil. Deposition of TiCU at 300 K leads to films which comprise Ti + and Ti species as inferred from XPS measurements [90]. Depending on the experimental parameters (background pressure of TiCU, electron flux, electron energy) different composition of Ti oxidation states are observed [23]. From angular-dependent measurements it was concluded that the Ti + centers are more prominent at the surface of the titanium chloride film, while the Xp+ centers are located in the bulk [90]. 

The 1 1 complex with titanium chloride or the 1 2 complex with beryllium chloride may explode violently. Careful pyrolysis of these gives mixtures of disulfur dinitride and its 1 1 complexes with the metal chlorides, which may also explode, so screening is essential. 

The Nef reaction can also be carried out with reducing agents. Aqueous titanium chloride reduces nitro compounds to imines, which are readily hydrolyzed to carbonyl compounds (Eq. 6.17).28 The Michael addition of nitroalkanes to enones followed by reaction with TiCl3 provides an excellent route to 1,4-diketones and hence to cyclopentenones. For example, cw-jasmone is readily obtained,28 as shown in Eq. 6.18. 

Tetraethyl orthotitanate, 22.9 g (0.100 mol), (Fluka Chemical Corporation, bulb-to-bulb-distilled at 110-115°C/0.1 mm) is dissolved in 80 mL of dry THF. Titanium chloride (TiCU) (Fluka Chemical Corporation), 19.0 g (0.100 mol, distilled at 136°C/atmospheric pressure) was added dropwise while cooling with an acetone/dry ice bath to keep the temperature below 0°C. Alternatively, TiCU may be added to a solution of Ti(OEl)4 (obtained from Aldrich Chemical Company, Inc.) in hexane at 0°C the solvent is evaporated and replaced by THF.3... 

Fig. 2. Sequential extraction of Arsenic (MG-magnesium chloride, PHOS-sodium hypo phosphate, HCL-hydrocihoric acid, OX-oxalic acid, ToCEB- titanium chloride with EDTA, NIT- nitric acid).

---