Carbon dioxide Fluoromethane

Hawthorne et al. [53] compared supercritical monochloride-fluoromethane, nitrogen dioxide and carbon dioxide for the extraction of polychlorobiphenyl from sediments. Monochlorodifluoro methane provided the highest recovery. Methanol modified carbon dioxide provided a 90% recovery of polychlorobiphenyls from sediments. 

As a rule xenon difluoride does not react with alkanes. Methane is oxidized by a water solution of xenon difluoride under high pressure (3.8 x 104"— 15.2 x 104 Torr) at 10-25 C in a special high-pressure reactor to form a mixture of methanol (4-8%), fluoromethane (1-2%) and carbon dioxide (25-50%).12... 

CARBON-TETRACHLORIDE TRICHLORO-FLUOROMETHANE OICHLORODI FLUOROMETHANE CHLOROTRI-FLUOROME7HANE CARBON-TETRAFLUORIDE CARBON MONOXIDE CARBON DIOXIDE CARBONYL-SULFIDE CARBON-DISULFIDE CHLOROFORM DICHLORO-FLUOROMETHANE CHLORODI-FLUOROMETHANE TRIFLUORO-METHANE TRIIODOMETHANE ISOTHIOCYANIC-ACID... 

Samples such as dichlorodifluoromethane, chlorotri-fluoromethane, and ethanol are separated by a conventional gas chromatograph column (Carbowax 20M) and are excited at the P32 line of the carbon dioxide laser (933cm ). The reported detection limit is an absorbance of 2.5 x 10 . ... 

SEC has also been used for the separation of phenols [105-107]. The supercritical fluid normally used is carbon dioxide with some modifier, for example, methanol or chlorodi-fluoromethane (Freon 22) [106]. Berger and Deye tested binary and tertiary supercritical mixtures, among them methanol/carbon dioxide mixtures containing very polar additives [107]. Ong et al. used chlorodifluoromethane as the supercritical fluid [105]. In most studies, UV detection was used and did not measure up to the required sensitivity. To bypass this problem, an online system with SPE cormected to the SFC instrmnentation was designed. Some of these systems are presented in the following section. 

Argon nitrogen carbon dioxide Trichloro fluoromethane Difluorodichloromethane Dichlorofluoromethane l-chloro,2-2 difluoroethane... 

Aerosol formulations, dilute pesticide formulations containing a volatile component (usually a fluoromethane, carbon dioxide, propane, or nitrous oxide) that propels the pesticide in fine droplets, are widely used in the home and garden. However, apprehension about ozone depletion in the stratosphere has led to the interdiction of many of the fluorocarbons so current aerosols employ largely carbon dioxide and propane. 

Lemmon, E. W, and Span, R., /. Chem. Eng. Data 51 785, 2006. [hydrogen sulfide, krypton, nitrous oxide, sulfur dioxide, xenon, carbon monoxide, carbon oxysulfide, R41-fluoromethane, neopentane]... 

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