Титана (IV) хлорид

Химические свойства

Description: Titanium tetrachloride is a noncombustible, colorless to light yellow liquid that fumes in air. Penetrating acrid odor.

Использование

Titanium tetrachloride is used as an intermediate in the manufacture of titanium metal, titanium dioxide, titanous chloride pigments, iridescent glass, and artificial pearls and as a starting material for a variety of organic and inorganic titanium compounds. It is also used as a dye, a polymerization catalyst, and as a catalyst in many organic syntheses because of it acidity and oxophilicity in many applications in the chemical industry. Titanium tetrachloride was formerly used as a smokeproducing screen with ammonia for the military; however, due to its extremely irritating and corrosive qualities in both liquid and smoke formulation, military applications are rarely used. The conversion of tetrachloride to titanium metal takes place by the reduction of chloride with magnesium which yields titanium metal and magnesium chloride and is referred to as the Kroll process after its inventor:
2 Mg ＋ TiCl4→2 MgCl2 ＋ Ti

Методы производства

TiCl4 is used in TiO2 production, the manufacture of artificial pearls and iridescent glass, and, by the military, to create smoke screens.

Общее описание

A colorless fuming liquid with a pungent odor. Corrosive to metals and tissue. Very toxic by inhalation.

Профиль реактивности

Titanium tetrachloride acts as an acid in aqueous solution. During the reduction of Titanium tetrachloride to titanium metal with potassium, an explosion occurred. The system had been heated to 90°C [Walter and Mandell 1967]. Addition directly to tetrahydrofuran caused a violent exothermic reaction [Inorg. Syn., 1982, 21, 135]. Ethylene can polymerize at low pressure if catalyzed by titanium halides. (Sundaram, K. M, M. M. Shreehan, E. F. Olszewski. thylene. Kirk-Othmer Encyclopedia of Chemical Technology. John Wiley & Sons, Inc. 2001.)

Опасность

Toxic by inhalation, strong irritant to skin and tissue.

Угроза здоровью

Titanium tetrachloride is a highly corrosive, acute irritant to the skin, eyes, mucous membranes and the respiratory tract. It is capable of causing death or permanent injury due to exposures encountered in normal use. Even short contact may lead to eye inflammation which may result in corneal opacities.

Пожароопасность

Material will react with water to produce hydrochloric acid. Titanium tetrachloride may ignite other combustible materials (e.g., wood, oil, etc.). Flammable, poisonous gases may accumulate in tanks and hopper cars. Runoff to sewer may create fire or explosion hazard. Reacts strongly with water to release hydrochloric acid and heat. Avoid water, moist air. Stable in concentrated aqueous solutions. Avoid contact with moisture; the chemical absorbs moisture from air and evolves dense white fumes.

Профиль безопасности

Poison by inhalation. A corrosive irritant to skin, eyes, and mucous membranes. When heated to decomposition it emits toxic fumes of Cl-. See also TITANIUM COMPOUNDS.

Возможный контакт

Used in the manufacture of titanium salts; mordant dye; titanium pigments; and used as a chemical intermediate for titanium metal; titanium dioxide; as an agent in smoke screens; polymerization catalyst; and iridescent agent in glass and pearl manufacturing.

Канцерогенность

Rats exposed to 10 mg TiCl4/m³ for 6 h/day, 5 days/week, for 2 years developed rhinitis, tracheitis, hyperplasia, foamy dust cell accumulation, and alveolar bronchiolization. In addition, 5/150 animals developed squamous cell carcinoma, compared to 0/156 in the controls. Two of the squamous cell carcinomas were described as cystic keratinizing lesions, whose relevance to humans was questioned by the authors. However, the remaining three squamous cell tumors were described as microscopic, well-differentiated carcinomas. Therefore, TiCl4 may be regarded as potentially carcinogenic in the rat.

Перевозки

UN1838 Titanium tetrachloride, Hazard class: 6.1; Labels: 6.1-Poison Inhalation Hazard, 8-Corrosive material, Inhalation Hazard Zone B.

Методы очистки

Reflux it with mercury or a small amount of pure copper turnings to remove the last traces of colour [due to FeCl3 and VCl4], then distil it under N2 in an all-glass system, taking precautions to exclude moisture. Clabaugh et al. [J Res Nat Bur Stand 55 261 1955] removed organic material by adding aluminium chloride hexahydrate as a slurry with an equal amount of water (the slurry being ca one-fiftieth the weight of TiCl4), refluxed it for 2-6hours while bubbling in chlorine, the excess of which is subsequently removed by passing a stream of clean dry air. The TiCl4 is then distilled, refluxed with copper and again distilled, taking precautions to exclude moisture. Volatile impurities are then removed using a technique of freezing, pumping and melting. The titanium tetrachloride 2-tetrahydrofuran complex [Beilstein 17/1 V 33.] M 333.9, has m 126-128o and is easier to handle than TiCl4 [Abrahamson et al. Organometallics 3 1379 1984]. [Baxter & Fertig J Am Chem Soc 45 1228 1923, Baxter & Butler J Am Chem Soc 48 3117 1926.] HARMFUL VAPOURS.

Несовместимости

Violent reaction with water or steam, releasing heat and hydrogen chloride fumes. Contact with moist air releases hydrogen chloride. Attacks many metals in presence of moisture.