With carbon tetrafluoride

In the presence of bromoform, an unexpected effect of the saturating gas was observed, the highest rate being observed with carbon tetrafluoride, then nitrogen, both being more efficient than the rare gases (Fig. 14). 

Tanaka, H. Hirano, T. Matsuzaki, A. (2003).Gas-phase Chemical Reaction of Laser Ablated Copper Atom with Carbon Tetrafluoride in Electric and Magnetic Fields. Transaction of the Materials Research Society of Japan, Vol.28, No.2, 0une 2003), pp. 275-278, ISSN 1382-3469... 

Carbon and Graphite. Fluorine reacts with amorphous forms of carbon, such as wood charcoal, to form carbon tetrafluoride [75-73-0], CF, and small amounts of other perfluorocarbons. The reaction initiates at ambient conditions, but proceeds to elevated temperatures as the charcoal bums ia fluoriae. 

Uses. The chemical inertness, thermal stability, low toxicity, and nonflammability of PFCs coupled with their unusual physical properties suggest many useflil applications. However, the high cost of raw materials and manufacture has limited commercial production to a few, small-volume products. Carbon tetrafluoride and hexafluoroethane are used for plasma, ion-beam, or sputter etching of semiconductor devices (17) (see loN implantation). Hexafluoroethane and octafluoropropane have some applications as dielectric gases, and perfluorocyclobutane is used in minor amounts as a dielectric fluid. Perfluoro-1,3-dimethyl cyclohexane is used as an inert, immersion coolant for electronic equipment, and perfluoro-2-methyldecatin is used for... 

Depending on the ring substituent, trifluoromethoxyben2enes can be made by the sequential chlorination—fluorination of anisole(s) (351—354). A one-step process with commercial potential is the BF (or SbF2)-cataly2ed reaction of phenol with carbon tetrachloride/hydrogen fluoride (355). Aryl trifluoromethyl ethers, which may not be accessible by the above routes,may be made by fluorination of aryl fluoroformates or aryl chlorothioformates with sulfur tetrafluoride (348) or molybdenum hexafluoride (356). 

In the absence of air, TEE disproportionates violently to give carbon and carbon tetrafluoride the same amount of energy is generated as in black powder explosions. This type of decomposition is initiated thermally and equipment hot spots must be avoided. The flammability limits of TEE are 14—43% it bums when mixed with air and forms explosive mixtures with air and oxygen. It can be stored in steel cylinders under controlled conditions inhibited with a suitable stabilizer. The oxygen content of the vapor phase should not exceed 10 ppm. Although TEE is nontoxic, it may be contaminated by highly toxic fluorocarbon compounds. 

Epoxides are regio- and stereoselectively transformed into fluorohydrins by silicon tetrafluoride m the presence of a Lewis base, such as diisopropyleth-ylamme and, m certain instances, water or tetrabutylammonium fluoride The reactions proceed under very mild conditions (0 to 20 C in 1,2-diohloroethane or diethyl ether) and are highly chemoselective alkenes, ethers, long-chain internal oxiranes, and carbon-silicon bonds remain intact The stereochemical outcome of the epoxide ring opening with silicon tetrafluoride depends on an additive used, without addition of water or a quaternary ammonium fluoride, as fluorohydrins are formed, whereas m the presence of these additives, only anti opening leading to trans isomers is observed [17, 18] (Table 2)... 

Carbon disulfide gives an essentially quantitative yield of carbon tetralluoride and sulfur on reaction with sulfur tetrafluoride at 450 C in the presence of arsenic trifluoride as a catalyst. At lower temperature, bis(fnfiuoromethyl) polysulfides are formed [//] (equation 15). 

Cyanogen gas, CjN has been found in foe gases of outer space. It can react with fluorine to form carbon tetrafluoride and nitrogen trifluoride. 

Model A cannot be eliminated definitely by the photographs there are, however, some points which make this model improbable. From the curve for this model the first minimum would be expected to be at least as well pronounced as the second minimum, whereas on the photographs the first minimum is not very well defined. That the qualitative appearance of the photographs supports model C rather than model A is further shown by the fact that the photographs resemble those of methyl nitrate more closely than those of carbon tetrafluoride. Some evidence is also provided by the radial distribution curve (Fig. 1), the first peak being displaced by 0.15 A. from the position expected for it for model A. For these reasons and the additional reason that it is difficult to correlate the tetrahedral configuration with an electronic structure involving only completed octets, we consider model A not to be satisfactory.7... 

Metallic uranium can be prepared from its oxides or hahdes by reduction at high temperature. Uranium dioxide, UO2, or other oxides such as UO3 or UsOs may be reduced to uranium metal by heating with carbon, calcium or aluminum at high temperatures. Similarly, uranium tetrafluoride or other halides can be reduced to metal by heating with sodium, potassium, calcium, or magnesium at high temperatures. Alternatively, uranium tetrafluoride mixed with fused alkali chlorides is electrolyzed to generate uranium metal. 

Carbon Disulfide under Sulfur Compounds Carbon Monoxide under Carbon Compounds Carbon Tetrachloride under Saturated Alkyl Halides Carbon Tetrafluoride under Saturated Alkyl Halides Carboxylic Acids Carboxylic Acids and Derivatives Carboxylic Acids with Other Functional Groups Cesium... 

Per luoroethylene),F3C CF2 mw 100.02 col gas, fr p -142.5°, bp -78.4° insol in w. Was prepd by Humiston (Refs 1 2) by treating charcoal with fluorine carbon tetrafluoride was obtd at the same time. Accdg to Ref 3, it can be prepd by passing chlorodifluoromethane thru a hot tube. Serves as a raw material for prepn of polytetrafluoroethylene polymers... 

Lebeau and Damiens, and Ruff and Keim, both reported isolation of carbon tetrafluoride as the major product of the reaction of fluorine with carbon at high temperatures. 

Miller. Calfee and Bigelow made 1,1,2,2-tetrachlorodifluorOethane from a vapor-phase reaction of fluorine/nitrogen mixtures with hexachloroethane or tetrachlorocthene over copper gauze. Calfee and Bigelow fluorinated ethane likewise, obtaining hexafluoroethane and carbon tetrafluoride. 

The first long-lived fluorine-containing carbocation was discovered by Olah and coworkers.32 Thus, the fluorodimethylcarbcnium ion [Me2CF+] was obtained by protonation of 2-fluoropropene and also from 2,2-difluoropropane by reaction with antimony(V) fluoride. In the course of these investigations it was found that a-F stabilizes a cationic state, whereas fi-F is destabilizing. Attempts to prepare the simplest member of this class, the trifluoromethyl carbocation CF3+ failed. The ionization of trifluoromethyl halides with antimony(V) fluoride at — 80 C yielded only carbon tetrafluoride. 

The other important factor to affect the operational conditions of the cell is the voltage increase between the carbon and copper lead. This problem has been solved individually in industry. For example, a 250 pm thick layer of nickel can be coated onto the upper part of the carbon anode using the atmospheric plasma spraying method.7 This electrode has been operated at 15 to 17 A dm-2 in a 1000 A scale industrial cell for 19 months. The cell voltage was 9.5 V and polarization did not occur with this electrode. Characteristic points of this new carbon electrode are low polarizability and no anode effect, and the concentration of carbon tetrafluoride contaminating the fluorine is below 2 ppm. 

Carbon fluoride [also known as carbon monofluoride, polycarbon monofluoride, graphite fluoride, or (CFx)n] is a solid, layered, non-stoichiometric fluorocarbon of empirical formula CFX, where 0 < x < 1.25, obtained by the action of elemental fluorine on carbon. Fluorine combines with carbon and yields three solid compounds CFX, C2FX, and C4FX as well as varying amounts of volatile fluorocarbons as byproducts. With appropriate selection of fluorination conditions nearly 100% conversion of carbon to carbon tetrafluoride can occur. 

As shown in Table 1, with stable fluorine flow rate, at ideal partial pressure, and with control of the fluorination time and temperature, the desired product composition with carbon yield up to 96% can be obtained. Fluorination of carbon above 500 C typically gives low yields due to further fluorination to carbon tetrafluoride as shown by the reaction mechanism below.12... 

The active carbon (C ), produced by the disproportionation reaction, reacts immediately with available fluorine producing more carbon tetrafluoride, which dilutes the fluorine concentration, thereby decreasing the rate of reaction.12 Formation of carbon tetrafluoride releases a large amount of heat (436 kJ moF ), thereby providing more energy to the product reactor to create more carbon tetrafluoride. This process can become uncontrolled when the entire reactor contents deflagrate and an explosive reaction can occur. 

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