Хлорэтан химические свойства, назначение, производство
Химические свойства
colourless gas
Физические свойства
Clear, colorless gas or liquid with a pungent or faint, sweetish ether-like odor. When spilled, ethyl
chloride evaporates quickly. Odor threshold concentration is 4.2 ppm (quoted, Amoore and
Hautala, 1983).
Использование
Chloroethane is a useful reactant in organic synthesis.
Показания
Chlorethane (ethyl chloride) is a highly flammable liquid that acts as a topical vapocoolant
to control pain associated with minor surgical procedures.When applied as
a spray, the product produces freezing of superficial tissues to ?20?C, which results
in insensitivity of peripheral nerve endings and local anesthesia that is maintained
up to 1 minute. Other coolant sprays can be used with the same effect.
Методы производства
Ethyl Chloride can be synthesized by treatment of ethyl alcohol with HCl, cleavage of diethylether with HCl in the presence of a catalyst (ZnCl2), chlorination of ethane or hydrochlorination of ethylene. The latter is the choice of industry. The reaction is carried out at 125 °F and 125 psi in the presence of AlCl3, which is dissolved in ethyl chloride.
Определение
A highly reactive manmade volatile organic com-
pound that is highly reactive in the atmosphere. It
readily reacts with oxidizing agents to release the
chlorine atoms which, circulate and cause tropo-
spheric ozone to decompose.
Общее описание
A clear colorless gas with a pungent odor. Flash point -58°F. Boiling point 54°F. Less dense than water and insoluble in water. Vapors are heavier than air. Under prolonged exposure to fire or heat the containers may rupture violently and rocket.Ethyl chloride is used as a solvent for oils,resins,and waxes. It is used in medicine and as an intermediate in synthesis.
Реакции воздуха и воды
Highly flammable. Insoluble in water.
Профиль реактивности
CHLOROETHANE is heat sensitive. CHLOROETHANE will hydrolyze in the presence of alkalis and water. CHLOROETHANE reacts with water or steam to produce toxic and corrosive fumes. CHLOROETHANE can also react vigorously with oxidizing materials. The vapor forms highly flammable mixtures with air. A mixture of CHLOROETHANE with potassium is shock-sensitive. Contact with chemically active metals such as Na, K, Ca, powdered Al, Zn and Mg may result in violent reactions.
Опасность
Highly flammable, severe fire and explosion risk; flammable limits in air 3.8–15.4%. Irritant
to eyes. Questionable carcinogen.
Угроза здоровью
Vapor causes drunkenness, anesthesia, possible lung injury. Liquid may cause frostbite on eyes and skin.
Химическая реактивность
Reactivity with Water: No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.
Профиль безопасности
Suspected carcinogen
with experimental carcinogenic and
neoplastigenic data. Mildly toxic by
inhalation. An irritant to sh, eyes, and mucous membranes. The liquid is harmful
to the eyes and can cause some irritation. In
the case of guinea pigs, the symptoms
attending exposure are similar to those
caused by methyl chloride, except that the
signs of lung irritation are not as
pronounced. It gives some warning of its
presence because it is irritating, but it is
possible to tolerate exposure to it until one
becomes unconscious. It is the least toxic
of all the chlorinated hydrocarbons. It can
cause narcosis, although the effects are
usually transient.
A very dangerous fire hazard when
exposed to heat or flame; can react
vigorously with oxidizing materials. Severe
explosion hazard when exposed to flame.
Reacts with water or steam to produce toxic
and corrosive fumes. Incompatible with
potassium. To fight fire, use carbon dioxide.
When heated to decomposition it emits
toxic fumes of phosgene and Cl-. See also
CHLORINATED HYDROCARBONS,
ALIPHATIC.
Возможный контакт
Ethyl chloride is used as an ethylating
agent in the manufacture of tetraethyl lead, dyes, drugs,
and ethyl cellulose; as a pharmaceutical, solvent; alkylating
agent; as a refrigerant and as a local anesthetic (freezing).
Канцерогенность
The EPA has not made a
carcinogenicity assessment as yet. However, the State of
California reviewed the carcinogenicity information.
CalEPA, using the NTP study, developed a cancer
potency estimate of 4.7E-3 per mg/kg/day and defined a No
Significance Risk Level (NSRL) of 1 50 μg/day.
Increased cancer of the uterus of female mice has been
produced by exposure to 15,000 ppm, but lower concentrations
have not been studied. Rats and mice were exposed to 0
or 15,000 ppm of ethyl chloride in an NTP 2-year study with
mixed results. Results in male rats were considered
equivocal based on a combined total of five skin tumors
versus none in the control male rats. Likewise, female rats’
results were considered equivocal because three astrocytomas
were found versus none in the female control rats. The
male mouse group had such poor survival that it was deemed
an inadequate study although combined alveolar/bronchiolar
adenomas and carcinomas were reported (10/48 versus 5/50
in the control male rats). Female mice exposed to 15,000 ppm
had clear evidence of an effect, for 43/50 mice had endometrial
uterine carcinomas versus 0/49 in the female control
mice. In addition, there was a suggestion of an increase in
combined hepatocellular adenomas and carcinomas in the
female mice (8/48 exposed versus 3/49 control). There is
clear evidence for carcinogenicity in female B6C3F1 mice
and equivocal evidence in male and female F344/N rats (high
incidence of uterine carcinomas.)
Экологическая судьба
Photolytic. The rate constant for the reaction of chloroethane and OH radicals in the atmosphere
at 300 K is 2.3 x 10-11 cm3/molecule?sec (Hendry and Kenley, 1979). At 296 K, a photooxidation
rate constant of 3.9 x 10-13 cm3/molecule?sec was reported (Howard and Evenson, 1976). The
estimated tropospheric lifetime is 14.6 d (Nimitz and Skaggs, 1992).
Chemical/Physical. Under laboratory conditions, chloroethane hydrolyzed to ethanol (Smith and
Dragun, 1984). An estimated hydrolysis half-life in water at 25 °C and pH 7 is 38 d, with ethanol
and HCl being the expected end-products (Mabey and Mill, 1978). Based on a measured
hydrolysis rate constant of 5.1 x 10-7 at 25 °C and pH 7, the half-life is 2.6 yr (Jeffers and Wolfe,
1996).
In air, formyl chloride is the initial photooxidation product (U.S. EPA, 1985). In the presence of
water, formyl chloride hydrolyzes to HCl and carbon monoxide (Morrison and Boyd, 1971).
Burns with a smoky, greenish flame releasing hydrogen chloride (Windholz et al., 1983).
In the laboratory, the evaporation half-life of chloroethane (1 mg/L) from water at 25 °C using a
shallow-pitch propeller stirrer at 200 rpm at an average depth of 6.5 cm was 23.1 min (Dilling,
1977).
At influent concentrations of 1.0, 0.1, and 0.01 mg/L, the GAC adsorption capacities at pH 5.3
were 0.59, 0.07, and 0.007 mg/g, respectively (Dobbs and Cohen, 1980).
Перевозки
UN1037 Ethyl chloride, Hazard Class: 2.1;
Labels: 2.1-Flammable gas. Cylinders must be transported
in a secure upright position, in a well-ventilated truck.
Protect cylinder and labels from physical damage. The
owner of the compressed gas cylinder is the only entity
allowed by federal law (49CFR) to transport and refill
them. It is a violation of transportation regulations to refill
compressed gas cylinders without the express written permission of the owner.
Методы очистки
Pass ethyl chloride through absorption towers containing, successively, conc H2SO4, NaOH pellets, P2O5 on glass wool, or soda-lime, CaCl2, P2O5. Condensed it into a flask containing CaH2 and fractionally distil it. It has also been purified by illumination in the presence of bromine at 0o using a 1000W lamp, followed by washing, drying and distilling. [Beilstein 1 IV 124.]
Несовместимости
Flammable gas. Slow reaction with
water; forms hydrogen chloride gas. Contact with moisture
(water, steam) forms hydrochloric acid and/or fumes of
hydrogen chloride. May accumulate static electrical
charges, and may cause ignition of its vapors. May form
explosive mixture with air. Contact with chemically active
metals: aluminum, lithium, magnesium, sodium, potassium,
zinc may cause fire and explosions. Attacks some plastics
and rubber.
Утилизация отходов
Return refillable compressed
gas cylinders to supplier. Incineration, preferably after mixing with another combustible fuel. Care must be exercised
to assure complete combustion to prevent the formation of
phosgene. An acid scrubber is necessary to remove the halo
acids produced.
Хлорэтан препаратная продукция и сырье
сырьё
препарат