Titanium chloride-sodium/alumina

General Considerations. The following chemicals were commercially available and used as received 3,3,3-Triphenylpropionic acid (Acros), 1.0 M LiAlH4 in tetrahydrofuran (THF) (Aldrich), pyridinium dichromate (Acros), 2,6 di-tert-butylpyridine (Acros), dichlorodimethylsilane (Acros), tetraethyl orthosilicate (Aldrich), 3-aminopropyltrimethoxy silane (Aldrich), hexamethyldisilazane (Aldrich), tetrakis (diethylamino) titanium (Aldrich), trimethyl silyl chloride (Aldrich), terephthaloyl chloride (Acros), anhydrous toluene (Acros), and n-butyllithium in hexanes (Aldrich). Anhydrous ether, anhydrous THF, anhydrous dichloromethane, and anhydrous hexanes were obtained from a packed bed solvent purification system utilizing columns of copper oxide catalyst and alumina (ether, hexanes) or dual alumina columns (tetrahydrofuran, dichloromethane) (9). Tetramethylcyclopentadiene (Aldrich) was distilled over sodium metal prior to use. p-Aminophenyltrimethoxysilane (Gelest) was purified by recrystallization from methanol. Anhydrous methanol (Acros) was... 

Sodium has been dispersed on the surface of alumina, sodium chloride, or titanium dioxide by stirring with excess support at 180-190°C under argon. The first was the most effective for reducing titanium(III) chloride for the McMurray reaction 5.1, being better than the commonly used reduction with zinc.17... 

Thus the reaction of sodium chloride with titanium from the alloy, or rutile from the scale leads to the formation of TiCl2, Na2Ti03, HC1 and Cl2.This list of reactions is by no means exhaustive, and may also involve reaction with other alloying additions which may be substituted for the titanium metal. Particularly, the role of aluminium must be of importance. A thermodynamic analysis by Travkin et al. [32] confirms that complex oxide scales are formed when titanium and its alloys react with NaCl. Particularly that the formation of volatile metallic chlorides are thermodynamically favourable, especially for alloying additions Zr, Mo and Al. The subsequent pyrohydrolysis of these metal chlorides results in the formation of HC1 gas, particularly with Mod., and AlClj. Furthermore, such pyrohydrolysis of halide salts may be accelerated by the presence of alumina within the scales, which acts as a catalyst [25]. 

Hypochlorites of sodium, calcium, and lithium, and chlorinated trisodium phosphate involve chlorine in their production. Sodium hypochlorite of about 5% strength finds extensive use in the household bleach market and in residential swimming pools, and 15% sodium hypochlorite, an industrial bleach, is used for water treatment in municipal and industrial plants. Sodium hypochlorite is made by reacting chlorine with caustic soda. Calcium hypochlorite is mainly used as a swimming pool chemical. Aluminum chloride, produced from chlorine and aluminum or alumina, is used as a catalyst (for alkyl and ethyl benzenes, dyestuffs, ethyl chloride, and hydrocarbon resin production) and also in the production of pharmaceuticals and titanium dioxide. 

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