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| | Chloromethane Basic information | | Uses |
| | Chloromethane Chemical Properties |
| Melting point | −97 °C(lit.) | | Boiling point | −24.2 °C(lit.) | | density | 0.915 g/mL at 25 °C(lit.) | | vapor density | 1.74 (vs air) | | vapor pressure | 3796 mm Hg ( 20 °C) | | refractive index | 1.0007 | | Fp | <-30 °F | | storage temp. | 2-8°C | | solubility | water: soluble5.32g/L at 25°C | | form | Colorless gas | | color | Colorless to Almost colorless | | Odor | faint sweet ethereal odor | | explosive limit | 19% | | Water Solubility | 5.347g/L(24.9 ºC) | | Merck | 14,6041 | | BRN | 1696839 | | Henry's Law Constant | In seawater: 5.22 at 5 °C, 6.36 at 10 °C, 8.72 at 15 °C, 9.35 at 20 °C, 11.20 at 25 °C (Moore,
2000) | | Exposure limits | TLV-TWA 50 ppm (～105 mg/m3) (ACGIH),
100 ppm (～210 mg/m3) (OSHA); ceiling
100 ppm (MSHA), 200 ppm (OSHA); TLV STEL 100 ppm (ACGIH); carcinogenicity:
Animal Inadequate Evidence, Human Inad equate Evidence (IARC). | | Stability: | Stable. May react violently or explosively with interhalogens, magnesium, zinc, potassium, sodium or their alloys. Incompatible with natural rubber and neoprene composites, but does not attack PVA. Highly flammable. May decompose upon exposure to moist air or water. | | CAS DataBase Reference | 74-87-3(CAS DataBase Reference) | | IARC | 3 (Vol. 41, Sup 7, 71) 1999 | | EPA Substance Registry System | Chloromethane (74-87-3) |
| | Chloromethane Usage And Synthesis |
| Uses | Methyl chloride is used as a catalyst carrier in the low-temperature polymerization of such products as the silicones and butyl and other types of synthetic rubber; as a refrigerant gas; and as a methylating agent in organic synthesis of such compounds as Grignard reagents, methyl ethers, and quaternary ammonium compounds.
Examples of products synthesized from methyl chloride are methyl mercaptan, methylene chloride, chloroform, carbon tetrachloride, and various bromochloro- and chlorofluoromethanes. It is also used as a chlorinating agent; as an extractant for greases, waxes, essential oils, and resins; as a low-temperature solvent; and as a fluid for thermometric and thermostatic equipment.
| | Description | 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. | | Chemical Properties | 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.
| | Chemical Properties | Methyl chloride is a colorless gas with
a faint, sweet odor which is not noticeable at dangerous
concentrations. The odor threshold is 10 ppm. Shipped
as a liquefied compressed gas. | | Physical properties | Colorless, liquefied compressed gas, with a sweet, ethereal odor. Volatile flammable gas. An
experimentally determined odor threshold concentration of >100 ppmv was reported by Leonardos
et al. (1969). | | Uses | Nearly equal amounts of methyl chloride are used in making these rubbers and the other principal user, production of tetramethyllead. | | Uses | 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. | | Uses | manufacture of silicones, tetramethyleads. Solvent catalyst for butyl rubber. Has been used as a refrigerant. | | Definition | ChEBI: A one-carbon compound that is methane in which one of the hydrogens is replaced by a chloro group. | | Production Methods | 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. | | Production Methods | Methyl chloride is also commercially produced by reaction of HCl on methanol in the presence of zinc chloride. Methyl chloride is mainly used in the production of silicone resins and rubbers. Silicon is reacted with an excess of methyl chloride at 300 °C in the presence of a copper catalyst. The product includes mono-, di-, and trichloromethyl silanes. Hydrolysis of the chloro groups converts them into the corresponding hydroxymethylsilanes. | | General Description | 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 Reactions | Highly flammable. | | Reactivity Profile | 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 causes nausea, vomiting, weakness, headache, emotional disturbances; high concentrations cause mental confusion, eye disturbances, muscular tremors, cyanosis, convulsions. Contact of liquid with skin may cause frostbite. | | 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. | | Fire Hazard | 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. | | Safety Profile | Suspected carcinogen.
Very mildly toxic by inhalation. An
experimental teratogen. Other experimental
reproductive effects. Human mutation data
reported. Human systemic effects by
inhalation: convulsions, nausea or vomiting,
and unspecified effects on the eye.
Methyl chloride has slight irritant
properties and may be inhaled without
noticeable discomfort. It has some narcotic
action, but this effect is weaker than that of
chloroform. Acute poisoning, characterized
by the narcotic effect, is rare in industry. In
exposures to high concentrations, dizziness,
drowsiness, incoordination, confusion,
nausea and vomiting, abdominal pains,
hiccoughs, diplopia, and dimness of vision
are followed by delirium, convulsions, and
coma. Death may be immediate; however, if
the exposure is not fatal, recovery is usually
slow. Degenerative changes in the central
nervous system are not uncommon. The
liver, hdneys, and bone marrow may be
affected, with resulting acute nephritis and
anemia. Death resulting from degenerative
changes in the heart, liver, and especially the
kidneys may occur several days after
exposure. Repeated exposure to low
concentrations causes damage to the central
nervous system and, less frequently, to the
liver, hdneys, bone marrow, and
cardiovascular system. Hemorrhages into
the lungs, intestinal tract, and dura have
been reported. Sprayed on the skin,
chloromethane produces anesthesia through
freezing of the tissues as it evaporates. Flammable gas. Very dangerous fire
hazard when exposed to heat, flame, or
powerful oxidizers. Moderate explosion
hazard when exposed to flame and sparks.
Explodes on contact with interhalogens
(e.g., bromine trifluoride, bromine
pentafluoride), magnesium and alloys,
potassium and alloys, sodium and alloys,
zinc. Potentially explosive reaction with
aluminum when heated to 152' in a sealed
container. Mxtures with aluminum chloride
+ ethylene react exothermically and then
explode when pressurized to above 30 bar.
May ignite on contact with aluminum
chloride or powdered aluminum. To fight
fire, stop flow of gas and use CO2, dry
chemical, or water spray. When heated to
decomposition it emits highly toxic fumes of
Cl-. See also CHLORINATED
HYDROCARBONS, ALIPHATIC. | | Potential Exposure | 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. | | Physiological effects | Methyl chloride is toxic, and areas where it is
handled must be adequately ventilated. It is
particularly dangerous in that it has no pronounced
odor to serve as a warning.
It acts as an anesthetic about one-fourth as
potent as chloroform, and also acts as a narcotic.
Inhalation must be avoided. Mild cases of
methyl chloride poisoning usually suffer from ataxia, lightheadedness, confusion, tremors,
nausea and vomiting, and frequently from anorexia
after a latent period of one-half to several
hours. Hiccough and constricting pain in the
neck may also be experienced. Visual disturbances
such as double vision are frequently reported.
Severe nonfatal poisonings are also characterized
by a latent period of several hours between
exposure and the onset of the first signs
or symptoms. This varies with individual susceptibility
and the intensity of exposure. Exposure
to high concentrations of several hundred
ppm or more leads successively to dizziness,
headache, vertigo, loss of coordination, nausea
and vomiting, abdominal pain, tremors, extreme
nervousness, mental confusion, convulsion,
unconsciousness, coma, and eventually death.
Rapid pulse, lowered blood pressure, elevated
body temperature, and rapid respiration are
among additional signs of exposure that may be
present. Some victims may show signs of liver
injury associated with jaundice and porphyrinuria,
and renal disturbances characterized by
albuminuria and oliguria, which may pass into
anuria. Complete recovery from severe
methyl chloride poisoning may take weeks or
months.
Fatal methyl chloride poisoning can have
symptoms similar to those of severe nonfatal
poisoning. Apparent recovery from what seems
a mild exposure through inhalation may be followed
by serious, prolonged or even fatal aftereffects
within a few days or weeks as a result of
cerebral and pulmonary edema and circulatory
failure. Repeated exposures are dangerous because
methyl chloride is eliminated slowly from
the body, where it is converted into hydrochloric
acid and methyl alcohol (wood alcohol).
ACGIH recommends a Threshold Limit
Value-Time-Weighted Average (TLV-TWA)
of 50 ppm (103 mg/m3
) for methyl chloride.
The TLV-TWA is the time-weighted average
concentration for a normal 8-hour workday and
a 40-hour workweek, to which nearly all workers
may be repeatedly exposed, day after day,
without adverse effect. ACGIH also recommends
a Threshold Limit Value-Short Term
Exposure Limit (TLV-STEL) of 100 ppm (207
mg/m3
) for methyl chloride. The TLV-STEL is
the 15-minute TWA exposure that should not be
exceeded at any time during a workday even if
the 8-hour TWA is within the TLV-TWA. Exposures
above the TLV-TWA up to the STEL
should not be longer than 15 minutes and should
not occur more than 4 times per day. There
should be at least 60 minutes between successive
exposures in this range .
OSHA lists an 8-hour Time-Weighted Average-
Permissible Exposure Limit (TWA-PEL)
of 100 ppm for methyl chloride. TWA-PEL is
the exposure limit that shall not be exceeded by
the 8-hour TWA in any 8-hour work shift of a
40-hour workweek. In addition, OSHA lists an
acceptable ceiling concentration of 200 ppm for
methyl chloride. The acceptable ceiling concentration
is the exposure limit that shall not be
exceeded at any time during an 8-hour shift.
Methyl chloride has an exception in that it has
an acceptable maximum peak above the acceptable
ceiling concentration of 300 ppm for an
8-hour shift as long as the maximum duration is
only once for 5 minutes in any hour.
Contact of methyl chloride liquid (or vapor in
a concentrated stream) with the skin or the eyes
must also be avoided, for such contact can result
in a condition resembling frostbite of the tissues. | | 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. | | Source | Drinking water standard: No MCLGs or MCLs have been proposed although methyl chloride
has been listed for regulation (U.S. EPA, 1996). In addition, 100 μg/L was recommended (U.S.
EPA, 2000). | | 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 cm3/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). | | Solubility in water | Miscible with chloroform, ether, glacial acetic acid (U.S. EPA, 1985), and other chlorinated
hydrocarbons including carbon tetrachloride. | | storage | 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. | | 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 | | Purification Methods | 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.] | | Incompatibilities | 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 | | GRADES AVAILABLE | Methyl chloride is available for commercial and
industrial use in various grades having much the
same component proportions from one producer
to another. Purities generally range from a
minimum of99.5 mole percent. |
| | Chloromethane Preparation Products And Raw materials |
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