Freons, halogenated hydrocarbon

PEI resists mineral acids, dilute bases (pH less than 9), freons, oils, greases, gasoline, most fuels, certain hydrocarbons and fully halogenated hydrocarbons, most cooking oils and greases, most detergents and disinfectants... 

For an assessment of the global distribution of persistent volatile halogenated hydrocarbons, the solubility and activity coefficients of such compounds in natural waters need to be known. Warner and Weiss (1985) have determined the solubilities of dichlorodifluoromethane (Freon 12) at 1 bar partial pressure at various temperatures in freshwater and in seawater (35.8%o salinity) ... 

Koppers Process (44). In the Koppers "Book Keeper" process, the books are treated with submicron particles of basic metal oxides, hydroxides, or salts of calcium, magnesium, or zinc. The particles can be applied in the paper making process or to the finished paper by electrostatic transfer such as in a xerographic process, by a dispersion in a gas, or by a suspension in an inert liquid. In the case of a liquid suspension of the particles, the liquids chosen are halogenated hydrocarbons. Typical liquids include Dupont Freon Fluorocarbons such as Freon 11 (trichloromonofluoromethane),... 

Silylated silica gel or low-activity (Grade III) silica gel are effective adsorbants, but even these can frequently cause decomposition of the very sensitive dioxetanes, even at — 50°C. In such cases Florisil can sometimes be useful. Eluant mixtures of halogenated hydrocarbons, for example, methylene chloride, carbon tetrachloride, fluorotrichloromethane (Freon-11), and alkanes, for example, -pentane, n-hexane, and cyclohexane, are quite effective and convenient, but their purity is critical, especially the absence of metal impurities. 

In veterinary practice many of the halogenated hydrocarbons such as carbon tetrachloride, hexachloroethane (CI3C-CCI3), isomeric difluorotetrachloroethanes (C2F2CI4), namely 1,2-difluorotetrachloroethane (FCI2C-CFCI2/ Freon 112) or 1,1-di-... 

The halogenated hydrocarbons are a related class of compounds. These are hydrocarbons, including alkanes, in which one or more of the hydrogen atoms have been replaced by some halogen — normally chlorine or bromine. Halogen substituents are named as chloro-, bromo-, and so on. Members of this class of compound include chloroform, once used as an anesthetic carbon tetrachloride, used at one time in dry cleaning solvent and freons (chlorofluorocarbons, CFCs), elements that have played a major role in the depletion of the ozone layer. See Chapter 18 for a discussion of CFCs and ozone. 

The naming system for halogenated hydrocarbons or simply halocarbons, originally commercialized as refrigerants under the trade name Freons by E.l. Du Pont de Nemours, was developed by T. Midgley, Jr. and A.L. Henne in 1929, and further refined by J.D. Park. The naming of the halocarbons was originally ... 

Also aluminum oxide coated ALOT columns can be used for CFC separations. However, the behavior of aluminum oxide depends on the composition of the sample to be aneilyzed. As discussed previously for the separation of vinyl chloride (see Section 7.5.1), there are a number of halogenated hydrocarbons which can decompose on the active aluminum oxide surface. Depending on the type of degradation products formed, the aluminum oxide will be partly deactivated and retention behavior will be difficult to reproduce. Fig. 7-45 shown an analysis of Freon 12 and Freon 11 in a mixture of hydrocarbons. The... 

FLUORINATED HYDROCARBONS. Fluorinated hydrocarbons are the most stable halogenated hydrocarbons and the most compatible with aluminum alloys. They have been used as propellants and refrigerants in contact with aluminum alloys in many applications. See "Freon and Halogenated Hydrocarbons."... 

Aluminum in a finely divided form, as in a powder, should not be expend to a halogenated hydrocarbon. The likelihood of creating a violent reaction that may lead to an explosion is increased when aluminum with a large surface area is exposed to a small volume of a halogenated hydrocarbon, and even more so when this operation is carried out under pressure. Specific entries in this book for fluorinated hydrocarbons such as Freons and inhibited halogenated hydrocarbons such as solvents (or degreasing illustrate applications with halogenated hydrocarbons. 

Volatile halogenated hydrocarbons, freons, nitrous oxides. Substances with low halogen contents (0, CI2) only have a low response (Table 2.38). 

Commonly used methods for the determination of petroleum hydrocarbon contamination in soil are modifications of Environmental Protection Agency method 418.1, which use sonication or a Soxhlet apparatus for analyte extraction and either infrared spectrometry [5] or gas chromatography with flame ionization detection [6-7] for extract analysis. Regardless of the analytical method following the extraction, both modifications use Freon-113, which has been implicated as a cause of ozone depletion. Therefore, alternative methods are being sought for the determination of hydrocarbon contamination in environmental samples that reduce the need for this halogenated solvent. 

Regardless of the analytical method used following the extraction, both modifications use Freon-113, which has been implicated as a cause of ozone depletion. Therefore, alternative methods are being sought for the determination of hydrocarbon contamination in environmental samples that reduce the need for this halogenated solvent. 

A carbon atom can be bonded to as many as four halogen atoms, so an enormous number of organic halides can exist. Completely fluorinated compounds are known as fluorocarbons or sometimes perfluorocarbons. The fluorocarbons are even less reactive than hydrocarbons. Saturated compounds in which all H atoms have been replaced by some combination of Cl and F atoms are called chlorofluorocarbons or sometimes freons. These compounds were widely used as refrigerants and as propellants in aerosol cans. However, the release of chlorofluorocarbons into the atmosphere has been shown to be quite damaging to the earth s ozone layer. Since January 1978, the use of chlorofluorocarbons in aerosol cans in the United States has been banned, and efforts to develop both controls for existing chlorofluorocarbons and suitable replacements continue. The production and sale of freons have been banned in many countries. 

Trichloroethylene. See Trichloroethylene 1,r-(2,2,2-Trichloroethylidene) bis (4-methoxybenzene). See Methoxychlor Trichloro ethylidene glycol. See Chloral hydrate Tri (2-chloroethyl) phosphate Tri-P-chloroethyl phosphate. See Tris (P-chloroethyl) phosphate Trichloroethylsilane Trichloroethylsilicane. See Ethyltrichlorosilane Trichlorofluoromethane CAS 75-69-4 EINECS/ELINCS 200-892-3 Synonyms CFC 11 F11 FC11 Fluorocarbon 11 Fluorotrichloromethane Freon 11 Freon HE Halocarbon 11 Methane, trichlorofluoro- Monofluorotrichloromethane Propellant 11 R11 Trichloromonofluoromethane Classification Halogenated aliphatic hydrocarbon... 

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