- FLUORINATION OF HYDROGEN-CONTAINING OLEFINS WITH ELEMENTAL FLUORINE
-
The hydrohalo-olefins cis and trans CHCl=CHCl, CHCl=CCl2, CHCl=CH-CH2Cl and CH2=CCl-CH2Cl have been fluorinated with elemental fluorine to give good yields of hydrohalofluoroalkanes.The best operational conditions for F2 addition to the double bond rather than hydrogen and/or chlorine atom substitution, dimerization and oligomerization of radical intermediates have been studied.Pleriminary studies on the reaction of Freon 12 and Freon 22 towards elemental fluorine have also been carried out.
- Conte, L.,Gambaretto, G. P.,Napoli, M.,Gervasutti, C.
-
-
Read Online
- PROCESS FOR THE FLUORINATION OF HALOOLEFINS
-
A process for the fluorination of haloolefins with elemental fluorine in the presence of anhydrous HF proceeds with high yield and selectivity in the product deriving from the addition of fluorine to the carbon-carbon double bond.
- -
-
Page/Page column 6
(2012/02/02)
-
- Kinetics and Mechanism of the Thermal Gas-phase Oxidation of Trichloroethene by Molecular Oxygen in Presence of Trifluoromethylhypofluorite, CF3OF
-
The oxidation of trichloroethene by molecular oxygen in presence of CF3OF has been studied at 293.8, 313.8 and 333.5 K.The initial pressure of CF3OF was varied between 0.8 and 9.5 Torr, that of CHClCCl2 between 5.4 and 54.6 Torr and that of O2 between 19.9 and 603.5 Torr.Several runs were made adding N2 at pressures varying from 96.4 to 663.2 Torr.The major product was CHCl2C(O)Cl, COCl2, HCl and CO were formed in minor amounts.Traces of CF3OCHClC(O)Cl, CHClFC(O)Cl, CF3OCHClCCl2F and CHClFCCl2F were detected.The oxidation is a chain reaction, whose rate increases with total pressure.The following mechanism, where E = CHClCCl2, R = CHClFCCl2, CF3OCHClCCl2 or CHCl2CCl2, R' = CHClF, CF3OCHCl or CHCl2 and M = effective pressure, explains the experimental results: (1) CF3OF + E = R + CF3O, (2) CF3O + E = R, (3,7) R + O2 + M = RO2 + M, (4,8) 2RO2 = 2RO + O2, (5,9) RO = R'C(O)Cl + Cl, (6) Cl + E = R, (10) 2R = recombination products, (11) R + CF3OF = RF + CF3O, (12) RO2 + E = RO2(E), (13) RO2(E) = products (e.g., R, HCl, CO, COCl2), k9 = 1.1 +/- 1E14 exp(-39.5 +/- 10 kJ mol-1/RT) s-1, k12 = 9.4 +/- 8E8 exp(-27.0 +/- 11 kJ mol-1/RT) dm3 mol-1 s-1. - Keywords: Gas-phase, Oxidation, Trichloroethene, Trifluoromethylhypofluorite, Chlorine atoms
- Czarnowski, J.
-
p. 103 - 118
(2007/10/03)
-
- The chlorination of 1,2-difluoroethane (HFC-152)
-
The photochlorination of CH2FCH2F yields CH2FCCl2F and CHClFCHClF, both of which were considered to be potential replacements for CFC-113 (CCl2FCF2Cl) based on their boiling points (48 deg C and 59 deg C, respectively).The CHClFCHClF/CH2FCCl2F ratio can be controlled by the choice of solvents.In aromatic solvents, the reactivity of the chlorine radical is reduced, increasing the amount of CH2FCCl2F produced.Relative rates in CCl4 and in the presence of water were compared to rates in aromatic solvents.Both CH2FCCl2F and CHClFCHClF failed in early toxicity tests and will thus not be pursued as HCFC replacements for CFC-113.
- Nappa, Mario J.,Sievert, Allen C.
-
p. 111 - 118
(2007/10/02)
-
- Catalytic Decomposition of CFC-112 and CFC-113 in the Presence of Ethanol
-
Iron (III) chloride supported on activated charcoal was extremely effective for decomposition of CFC-112 and CFC-113 into CO and CO2 in the presence of ethanol at the low temperature.
- Miyatani, Daisaku,Shinoda, Kiyonori,Nakamura, Tadashi,Ohta, Minoru,Yasuda, Kensei
-
p. 795 - 798
(2007/10/02)
-
