Бора трихлорид химические свойства, назначение, производство
Описание
Boron trichloride is a colorless, acid gas that
fumes in the presence of moist air. It is packaged
in steel cylinders as a liquid under its own
vapor pressure of 19.1 psia (132 kPa, abs) at
70°F
(21.1°C). It reacts with water or moist air to
produce hydrochloric and boric acid.
Химические свойства
Boron trichloride is a colorless gas with a pungent odor. It reacts violently with water, and on decomposition and hydrolysis yields hydrochloric and boric acid. It has a pungent, highly irritating odor. Occupational exposure to boron and boron compounds can occur in industries that produce special glass, washing powder, soap and cosmetics, leather, cement, etc.
Использование
Boron trichloride is used in the refining of aluminum,
copper, magnesium, and zinc to remove
oxides, nitrides, and carbides trom the molten
metal. Carbon monoxide, hydrogen, and nitrogen
can be removed from an aluminum melt by
treating with boron trichloride. It also improves
the tensile strength of aluminum and will allow
remelting without a major change in the grain
structure.
The electronic industry benefits trom boron
trichloride in many applications. It is used in the
production of optical fibers, as a p-type dopant
for thermal diffusion in silicon, and for ion implantation.
прикладной
One of the most important uses of Boron trichloride is in the preparation of boron
fibers ( Fibers, 13. Refractory Fibers). Typically an electrically heated tungsten filament is
passed through a chamber containing BCl3 and
hydrogen. The BCl3 is reduced, and boron is
deposited on the filament, producing a stiff,
strong boron fiber.Boron trichloride, like the trifluoride, has been
used as a Lewis acid catalyst in organic synthesis
in the polymerization of olefins and phosphazines, as well as in catalysis of other organic
reactions. Boron trichloride is also used in plasma etching of aluminum and silicon, in semiconductor manufacturing, and as a source of boron
for chemical vapor deposition. Steel is boronized
by contacting it with a reactive mixture of hydrogen, hydrocarbons, and BCl3 at high
temperatures.
Общее описание
Boron trichloride appears as a colorless gas with a pungent odor. Fumes irritate the eyes and mucous membranes. Corrosive to metals and tissue and is toxic. Under prolonged exposure to fire or intense heat, the containers may rupture violently and rocket. Used as a catalyst in chemical manufacture, in soldering fluxes, and for many other uses.
Реакции воздуха и воды
Fumes in air, including moisture in air and soil, to form hydrochloric acid [Merck 11th ed. 1989]. Reacts vigorously with water and forms hydrochloric acid fumes and boric acid.
Профиль реактивности
Boron trichloride vigorously attacks elastomers and packing materials. Contact with Viton, Tygon, Saran and natural and synthetic rubbers is not recommended. Highly corrosive to most metals in the presence of moisture. Reacts energetically with nitrogen dioxide/dinitrogen tetraoxide, aniline, phosphine, triethylsilane, or fat and grease [Mellor 5:132 1946-47]. Reacts exothermically with chemical bases (examples: amines, amides, inorganic hydroxides).
Пожароопасность
When heated to decomposition, Boron trichloride emits toxic fumes of chlorides. Boron trichloride will react with water or steam to produce heat, and toxic and corrosive fumes. In hot water, decomposes to hydrochloric acid and boric acid. Fumes and hydrolyzes in moist air to form hydrochloric acid and oily, irritating corrosives. Avoid aniline, hexafluorisopropylidene amino lithium, nitrogen dioxide, phosphine, grease, organic matter, and oxygen. Nitrogen peroxide, phosphine, fat or grease react energetically with Boron trichloride . Oxygen and Boron trichloride react vigorously on sparking. Boron trichloride and aniline react violently in the absence of a coolant or diluent. Stable.
Возможный контакт
Used in refining of aluminum, magnesium,
copper alloys, and in polymerization of styrene.
Manufacture and purification of boron; catalyst in organic
reactions; semiconductors; bonding of iron or steel; purification
of metal alloys to remove oxides, nitrides, and
carbides; chemical intermediate for boron filaments; soldering
flux; electrical resistors; and extinguishing magnesium
fires in heat treating furnaces.
хранилище
Boron trichloride cylinders should be protected from physical damage. The cylinders
should be stored upright and fi rmly secured to prevent falling or being knocked over,
in a cool, dry, well-ventilated area of non-combustible construction away from heavily
traffi cked areas and emergency exits
Методы очистки
Purify it (from chlorine) by passage through two mercury-filled bubblers, then fractionally distil it under a slight vacuum. In a more extensive purification the nitrobenzene addition compound is formed by passage of the gas over nitrobenzene in a vacuum system at 10o. Volatile impurities are removed from the crystalline yellow solid by pumping at -20o, and the BCl3 is recovered by warming the addition compound at 50o. Passage through a trap at -78o removes entrained nitrobenzene, the BCl3 finally condensing in a trap at -112o [Brown & Holmes J Am Chem Soc 78 2173 1956]. Also purify it by condensing it into a trap cooled in acetone/Dry-ice, where it is pumped for 15minutes to remove volatile impurities. It is then warmed, recondensed and again pumped. [Gamble Inorg Synth III 27 1950.] TOXIC.
Несовместимости
Incompatible with lead, graphiteimpregnated
asbestos, potassium, sodium. Vigorously
attacks elastomers, packing materials, natural and synthetic
rubber; viton, tygon, saran, silastic elastomers.
Avoid aniline, hexafluorisopropylidene amino lithium,
nitrogen dioxide, phosphine, grease, organic matter; and
oxygen. Nitrogen peroxide, phosphine. Fat or grease
react vigorously with boron trichloride. It reacts with
water or steam to produce heat, boric acid, and corrosive
hydrochloric acid fumes. Oxygen and boron trichloride
react vigorously on sparking. Attacks most metals in the
presence of moisture.
Утилизация отходов
Return refillable compressed
gas cylinders to supplier. Nonrefillable cylinders should be
disposed of in accordance with local, state, and federal regulations.
Allow remaining gas to vent slowly into atmosphere
in an unconfined area or exhaust hood. Refillabletype
cylinders should be returned to original supplier with
any valve caps and outlet plugs secured and valve protection
caps in place.
Меры предосторожности
Boron trichloride vigorously attacks elastomers and packing materials, natural and synthetic rubbers. It also reacts energetically with nitrogen dioxide/dinitrogen tetraoxide, aniline, phosphine, triethylsilane, or fat and grease. It reacts exothermically with chemical
bases such as amines, amides, and inorganic hydroxides. Occupational workers should
use gloves of neoprene or butyl rubber, PVC or polyethylene, safety goggles, or glasses and
face shield, and safety shoes.
Бора трихлорид препаратная продукция и сырье
сырьё
препарат