Chlormethan Chemische Eigenschaften,Einsatz,Produktion Methoden
ERSCHEINUNGSBILD
FARBLOSES VERFLüSSIGTES GAS.
PHYSIKALISCHE GEFAHREN
Das Gas ist schwerer als Luft und kann sich am Boden ausbreiten. Fernzündung möglich,. Es kann sich in tiefer gelegenen Bereichen sammeln und den Luftsauerstoff verdrängen.(S. Anm.)
CHEMISCHE GEFAHREN
Zersetzung beim Verbrennen unter Bildung giftiger und ätzender Rauche mit Chlorwasserstoff und Phosgen Reagiert sehr heftig mit pulverförmigem Aluminium, pulverförmigem Zink, Aluminiumtrichlorid und Ethylen unter Feuer- und Explosionsgefahr. Greift viele Metalle in Gegenwart von Feuchtigkeit an.
ARBEITSPLATZGRENZWERTE
TLV: 50 ppm (als TWA); 100 ppm (als STEL); Hautresorption; Krebskategorie A4 (nicht klassifizierbar als krebserzeugend für den Menschen); (ACGIH 2005).
MAK: 50 ppm, 100 mg/m? Spitzenbegrenzung: überschreitungsfaktor II(2); Hautresorption; Krebserzeugend Kategorie 3B; Schwangerschaft: Gruppe B; (DFG 2005).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation und über die Haut.
INHALATIONSGEFAHREN
Eine gesundheitsschädliche Konzentration des Gases in der Luft wird beim Entweichen aus dem Behälter sehr schnell erreicht.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION: Die Flüssigkeit kann Erfrierungen hervorrufen. Möglich sind Auswirkungen auf das Zentralnervensystem. Exposition kann zu Bewusstlosigkeit führen. Exposition weit oberhalb der Arbeitsplatzgrenzwerte kann zu Schäden der Leber, des Herzkreislaufsystems und der Nieren führen. ärztliche Beobachtung notwendig.
WIRKUNGEN NACH WIEDERHOLTER ODER LANGZEITEXPOSITION
Möglich sind Auswirkungen auf das Zentralnervensystem mit nachfolgenden Auswirkungen, festgehalten durch Verhaltenstests. Tierversuche zeigen, dass die Substanz möglicherweise fruchtbarkeitsschädigend oder entwicklungsschädigend wirken kann.
LECKAGE
Gefahrenbereich verlassen! Fachmann zu Rate ziehen! Belüftung. Wasserstrahl NIEMALS auf die Flüssigkeit richten. Persönliche Schutzausrüstung: Vollschutzanzug mit umgebungsluftunabhängigem Atemschutzgerät.
R-Sätze Betriebsanweisung:
R12:Hochentzündlich.
R40:Verdacht auf krebserzeugende Wirkung.
R48/20:Gesundheitsschädlich: Gefahr ernster Gesundheitsschäden bei längerer Exposition durch Einatmen.
R67:Dämpfe können Schläfrigkeit und Benommenheit verursachen.
R66:Wiederholter Kontakt kann zu spröder oder rissiger Haut führen.
R22:Gesundheitsschädlich beim Verschlucken.
R19:Kann explosionsfähige Peroxide bilden.
R38:Reizt die Haut.
R23/25:Giftig beim Einatmen und Verschlucken.
R11:Leichtentzündlich.
S-Sätze Betriebsanweisung:
S9:Behälter an einem gut gelüfteten Ort aufbewahren.
S16:Von Zündquellen fernhalten - Nicht rauchen.
S33:Maßnahmen gegen elektrostatische Aufladungen treffen.
S29:Nicht in die Kanalisation gelangen lassen.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S24:Berührung mit der Haut vermeiden.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S7:Behälter dicht geschlossen halten.
Beschreibung
Methyl chloride is a colorless, flammable gas
with a faintly sweet, nonirritating odor at room
temperature. It is shipped as a transparent liquid
under its vapor pressure of about 59 psig at
70°F (407 kPa at 21.1℃）.
Methyl chloride burns feebly in air, but forms
mixtures with air that can be explosive within its
flammability range.
Dry methyl chloride is very stable at normal
temperatures and in contact with air. In the
presence of moisture, it hydrolyzes slowly,
which results in the formation of corrosive hydrochloric
acid. At temperatures above 700°F
(371℃）, methyl chloride may decompose into
toxic end-products (hydrochloric acid, phosgene,
chlorine, and carbon monoxide). It is
slightly soluble in water and very soluble in
alcohol, mineral oils, chloroform, and most organic
liquids.
Chemische Eigenschaften
Methyl chloride,CH3CI, is a flammable, narcotic,colorless compressed gas or liquid with a faintly sweet odor.Slightly soluble in water and soluble in alcohol this gas boils at -23.7℃ and freezes at -97.6℃ and is used as a refrigerant, catalyst carrier, and methylating agent. Also known as chloromethane.
Physikalische Eigenschaften
Colorless, liquefied compressed gas, with a sweet, ethereal odor. Volatile flammable gas. An
experimentally determined odor threshold concentration of >100 ppm
v was reported by Leonardos
et al. (1969).
Verwenden
Methyl chloride is used as a refrigerant,as a local anesthetic, as a blowing agentfor polystyrene foams, and as a methylat ing agent in the synthesis of a number ofchemicals of commercial application.
Definition
ChEBI: A one-carbon compound that is methane in which one of the hydrogens is replaced by a chloro group.
Vorbereitung Methode
Methyl chloride has been used in rubber adhesives and other
rubber solutions; in the pharmaceutical industry; as a paint
and varnish remover; in solvent degreasing; in aerosol
2 JON B. REID AND CUSTODIO V. MUIANGA formulations; in food and drug processing; in the plastics
industry; in hair sprays, insecticides, and spray paints; as a
cosolvent or vapor pressure depressant; as a blowing agent
for flexible polyurethane foams; as a cleaning solvent for
printed circuit boards; as a stripper solvent for photoresists;
as a solvent for cellulose acetate fiber; in plastic film; in
protective coatings; in chemical processing; as a carrier
solvent for herbicides and insecticides; to extract heatsensitive,
naturally occurring substances such as cocoa,
edible fats, spices, and beer hops; for decaffeinating coffee;
as a refrigerant; in oil dewaxing; as a dye and perfume
intermediate; in the textile industry; as a postharvest fumigant
for strawberries; as a grain fumigant; for degreening
citrus fruits; as an industrial solvent; in low-temperature
extraction; as a solvent for oil, fats, bitumen, esters, resins,
and rubber; in coating photographic films; as a food additive;
in synthetic fibers and leather coatings; as a spotting agent;
and in organic synthesis.
Allgemeine Beschreibung
A colorless gas with a faint sweet odor. Shipped as a liquid under its vapor pressure. A leak may either be liquid or vapor. Contact with the liquid may cause frostbite by evaporative cooling. Easily ignited. Vapors heavier than air. Can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket. Used to make other chemicals and as a herbicide.
Air & Water Reaktionen
Highly flammable.
Reaktivität anzeigen
METHYL CHLORIDE can react vigorously with oxidizing agents. May react explosively with sodium, potassium, sodium-potassium alloy, magnesium, zinc. Reacts with aluminum powder in the presence of catalytic amounts of aluminum chloride to form pyrophoric trimethylaluminum. When heated to decomposition, METHYL CHLORIDE emits highly toxic fumes of chlorine [Bretherick, 5th ed., 1995, p. 176].
Hazard
Flammable, dangerous fire risk, explosive
limits in air 10.7–17%. Narcotic. Psychic effects.
Central nervous system impairment; liver, kidney and testicular damage, and teratogenic effects.
Questionable carcinogen.
Health Hazard
Inhalation of methyl chloride can produceheadache, dizziness, drowsiness, nausea,vomiting, convulsions, coma, and respiratoryfailure. It is narcotic at high concentrations.Repeated exposures can produce liver and Methyl chloride caused adverse reproduc tive effects in test animals. These includeembryo toxicity, fetal death, developmentalabnormalities, and paternal effects in rats andmice. It tested positive to the histidine rever sion–Ames test for mutagenicity. The car cinogenic properties of this compound havenot been established. The evidence in ani mals and humans is inadequate.
Brandgefahr
Flammable gas, burns with a smoky flame;
autoignition temperature 632°C (1170°F).
Methyl chloride forms explosive mixtures
with air within the range 7.6–19.0% by
volume in air. It reacts explosively with
alkali metals, potassium, sodium, or lithium;
sodium–potassium alloy; and with magnesium, aluminum, or zinc in powder form.
Materials Uses
Dry methyl chloride may be contained in such
common metals as steel, iron, copper, and
bronze, but it has a corrosive action on zinc,
aluminum, die castings, and possibly magnesium
alloys. Methyl chloride must not be used
with aluminum, since in the presence of moisture
it forms spontaneously flammable methyl
aluminum compounds upon contact with that
metal. No reaction occurs, however, with the
drying agent, activated alumina.
Gaskets made of natural rubber and many
neoprene compositions should be avoided because
methyl chloride dissolves many organic
materials. Pressed fiber gaskets, including those
made of asbestos may be used with methyl chloride.
Polyvinyl alcohol is unaffected by methyl
chloride, and its use is also recommended. Medium-
soft metal gaskets may be used for applications
where alternating stresses such as those resulting from large temperature changes do not
lead to "ironing out" and consequent leakage.
mögliche Exposition
Methyl chloride is used as a methylating and chlorinating agent in organic chemistry; Used in
production of silicones and tetramethyl lead. In petroleum
refineries it is used as an extractant for greases, oils, and
resins. Methyl chloride is also used as a solvent in the synthetic rubber industry; as a refrigerant; and as a propellant
in polystyrene foam production. In the past it has been used
as a local anesthetic (freezing). It is an intermediate in drug
manufacture.
Carcinogenicity
Methyl chloride was mutagenic to bacteria
and genotoxic in a number of mammalian cell
systems in vitro.14 It gave positive results in the
dominant lethal test in rats in vivo.
NIOSH recommends that methyl chloride
be considered a potential occupational teratogen
and carcinogen.
The IARC states that there is inadequate
evidence for the carcinogenicity of methyl
chloride to experimental animals and humans.
Environmental Fate
Biological. Enzymatic degradation of methyl chloride yielded formaldehyde (Vogel et al.,
1987).
Photolytic. Reported photooxidation products via OH radicals include formyl chloride, carbon
monoxide, hydrogen chloride, and phosgene (Spence et al., 1976). In the presence of water, formyl
chloride hydrolyzes to HCl and carbon monoxide, whereas phosgene hydrolyzes to hydrogen
chloride and carbon monoxide (Morrison and Boyd, 1971).
Methyl chloride reacts with OH radicals in the atmosphere at a rate of 8.5 x 10
-14 cm
3/sec with a
lifetime of 135 d (Cox et al., 1976).
Chemical/Physical. The estimated hydrolysis half-life at 25 °C and pH 7 is 0.93 yr (Mabey and
Mill, 1978).
The evaporation half-life of methyl chloride (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 27.6 min (Dilling, 1977).
Lager
All personnel handling methyl chloride cylinders
should be fully informed about the dangers
that can arise from improper handling of methyl
chloride. The cylinder and system should be
grounded before use. Before introducing methyl
chloride into any apparatus or equipment, it
should be tested for leaks, all leaks repaired,
and the apparatus thoroughly dried. Only
nonsparking tools should be used with methyl
chloride. Chemical safety goggles and/or a
full-face shield should be used when handling
liquid methyl chloride.
Versand/Shipping
UN1063 Methyl chloride, or Refrigerant gas
R 40, 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
läuterung methode
Bubble methyl chloride through a sintered-glass disc dipped into conc H2SO4, then wash it with water, condense it at low temperature and fractionally distil it. It has been distilled from AlCl3 at -80o. Alternatively, pass it through towers containing AlCl3, soda-lime and P2O5, then condense and fractionally distil it. Store it as a gas. [Beilstein 1 IV 28.]
Inkompatibilitäten
Violent reaction with chemically active
metals, such as potassium, powdered aluminum; zinc, and
magnesium. Reaction with aluminum trichloride, ethylene.
Reacts with water (hydrolyzes) to form hydrochloric acid.
Attacks many metals in the presence of moisture
Waste disposal
Return refillable compressed
gas cylinders to supplier. Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform to EPA regulations governing
storage, transportation, treatment, and waste disposal.
Controlled incineration with adequate scrubbing and ash
disposal facilities
Chlormethan Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
5-Methyl-2-pyridylamin
coconutaminium trimethyl chloride
Faropenem sodium hemipentahydrate
1-[Diphenyl[3-(trifluormethyl)phenyl]methyl]-1H-1,2,4-triazol
Trimethyloctadecylammoniumchlorid
4，4-dimethyl isoxazolidin-3-one
Hydroxypropyl methyl cellulose
Polyethylene glycol dimethyl ether
Methyl cellulose
Dichlor(methyl)silan
1,7-Bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-dien-3,5-dion
Chlortrimethylsilan
Clethodim
α-Butyl-α-phenyl-1H-imidazol-1-propiononitril
2,4-Pentadienal
Trichlor(methyl)silan
1,2-Dimethoxybenzol
Auranofin
Dicamba
2-chloro-3-isothiocyanato-prop-1-ene
Polycarbonate
Imazosulfuron
butyl rubber
Methanthiol
1,1-Dimethylpiperidiniumchlorid
Fipronil
Cefdinir
2-Ethylhexyl-10-ethyl-4,4-dimethyl-7-oxo-8-oxa-3,5-dithia-4-stannatetradecanoat
1,2,4,5-Tetramethylbenzol
Dichlor(dimethyl)silan
Succinyldichlorid
Chlor(methyl)silan
