Methyl chloride, refrigeration

Uses. Intermediate in the manufacture of acrylic acid herbicide algicide in pharmaceuticals, perfumes, food supplements, and resins as a warning agent in methyl chloride refrigerating systems... 

Dose-related pharmacodynamic action on normal cells e.g. lead, benzene, phenylhydrazine, chlorates (weed-killer), methyl chloride (refrigerant), some snake venoms. 

ORIGIN/INDUSTRY SOURCES/USES pesticides plastics perfumes colloidal forms of metals organic synthesis glycerin acrylic acid esters warning agent in methyl chloride refrigerant military poison mixtures aquatic herbicide liquid fuel algae and aquatic weed control slimicide in paper manufacture... 

E. Functional group with halogen —X alkyl or aryl halide CH3CI methyl chloride, refrigerant and local anesthetic... 

Table 1 lA presents tabulations of the safety of important refrigerants, but this list does not include aU available refrigerants. Table 11-5 summarizes a limited list of comparative hazards to life of refrigerant gas and vapor. The current more applicable refrigerants from the m or manufacturers of the CFC and HCFC refrigerants and their azeotropes/ blends/mrxtures are included, but the list excludes the pure hydrocarbons such as propane, chlorinated hydrocarbons such as methyl chloride and others, inorganics, ammonia, carbon dioxide, etc. See Table 11-6. The CFC compounds have a longer and more serious ozone depletion potential than the HCFC compounds, because these decompose at a much lower atmospheric level and have relatively short atmospheric lifetimes therefore, they do less damage to the ozone layer. Table 11-7 summarizes alternate refrigerants of the same classes as discussed previously. Table 11-8 correlates DuPont s SUVA refrigerant numbers to the corresponding ASHRAE numbers.

The major use of methyl chloride is to produce silicon polymers. Other uses include the synthesis of tetramethyl lead as a gasoline octane booster, a methylating agent in methyl cellulose production, a solvent, and a refrigerant. 

One of the major problems inherent in the manufacture and use of early refrigerators was that all of the heat exchange media on which they operated—ammonia, butane, sulfur dioxide, and methyl chloride, for example—were either toxic or flammable. Until this problem was overcome, selling consumers on the idea of home refrigeration units posed some serious challenges. 

Moissan finally used as electrolyte a solution of dry potassium acid fluoride in anhydrous hydrofluoric acid. His apparatus consisted of two platinum-iridium electrodes sealed into a platinum U-tube closed with fluorspar screw caps covered with a layer of gum lac (42, 49, 59). The U-tube was chilled with methyl chloride, the gas now used in many modem refrigerators, to a temperature of —23°. 

Methyl chloride is used in the production of tetramethyllead antiknock compounds for gasoline and methyl silicone resins and polymers, and as a catalyst carrier in low-temperature polymerization (e g., butyl rubber), a refrigerant, a fluid for thermometric and thermostatic equipment, a methylating agent in organic synthesis, an extractant and low-temperature solvent, a herbicide, a topical antiseptic, and a slowing agent (lARC, 1986 Lewis, 1993). 

Artie [Du Pont], TM for refrigeration grade of methyl chloride. 

Kegel AH, McNally WD, Pope AS Methyl chloride poisoning from domestic refrigerators. JAMA 93 353-358, 1929... 

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