353-50-4Relevant articles and documents
Kinetics of the Reactions of CF3Ox Radicals with NO, O3, and O2
Turnipseed, Andrew A.,Barone, Stephen B.,Ravishankara, A. R.
, p. 4594 - 4601 (1994)
The technique of pulsed laser photolysis/pulsed laser-induced fluorescence detection of CF3O was used to study the stratospherically important reactions of CF3O radicals with NO (k5), O3 (k4), and O2 (k6) and that of CF3OO
Atmospheric degradation mechanism of CF3OCF2H
Inoue,Kawasaki,Wallington,Hurley
, p. 296 - 302 (2001)
Smog chamber/FTIR techniques were used to study the Cl atom initiated oxidation of CF3OCF2H in 700 Torr of N2/O2 at 295±2K. Atmospheric oxidation of CF3OCF2H proceeds via the formation of C
Tropospheric degradation products of novel hydrofluoropolyethers
Tuazon, Ernesto C.
, p. 1817 - 1821 (1997)
The Cl atom-initiated photooxidations of the hydrofluoropolyethers (HFPEs) HCF2OCF2OCF2CF2OCF2H, HCF2OCF2CF2OCF2H, and HCF2OCF2OCF2H in air produced C(O)F2 as the only carbon-containing product, with observed average C(O)F2 molar formation yields of 4.73, 3.77, and 2.82, respectively. The C(O)F2 molar formation yields during the early stages of the reactions were observed to be closer to the number of C atoms in each parent HFPE. On the basis of current knowledge concerning the degradation pathways of hydrofluorocarbons and hydrochlorofluorocarbons, it is expected that C(O)F2 will also be produced with near unit yield per C atom from the above HFPEs in the troposphere, where loss processes would be initiated primarily by reaction with OH radicals. The rate constants for reaction with the Cl atom at 298 ± 2 K were determined for the HFPEs by a relative rate method that employed CF3CF2H as the reference compound [κ(Cl + CF3CF2H) = (2.4 ± 0.5) x 10-16 cm3 molecule-1 S-1], with measured values of (in units of 10-17 cm3 molecule-1 s-1) HCF2OCF2OCF2CF2OCF2H, 3.6 ± 0.8; HCF2OCF2CF2OCF2H, 4.5 ± 1.0; and HCF2OCF2OCF2H, 5.0 ± 1.1.
Reaction Modulation Spectroscopy: A New Approach to Quantifying Reaction Mechanisms
Donahue, Neil M.,Demerjian, Kenneth L.,Anderson, James G.
, p. 17855 - 17861 (1996)
We report a new experimental method, reaction modulation spectroscopy, (RMS) that, shows great promise in enabling the systematic analysis of complicated oxidation mechanisms over the full range of atmospheric pressures and temperatures.The method is a form of difference spectroscopy in which we employ FTIR absorption spectroscopy in a high-pressure flow system (HPFS) where a plume of reacting species is examined before any significant fraction reaches the tube wall.The onest of the reaction is modulated by modulating the flow of an initiating radical species over a period that is short compared to any associated with experimental drifts.Spectra obtained with the radical source on and off are ratioed, giving a transmittance spectrum showing only the effects of the reaction modulation.The system is in a steady state, so signal averaging over long periods (up to several days) may be employed, if necessary, to obtain a high signal-to-noise ratio.Because no bulk reagents are disturbed in the process, we observe extremaly precise conservation of mass in the reaction plume.We illustrate the technique for the system OH + C3F6 (+O2, NOx,...) -> -> CF2O + CF3CFO, where we observe nearly 100percent conservatioin of odd-nitrogen species and roughly 90percent conservation of carbon under conditions chosen to force the reaction to completion, with residual spectra consistent with unidentified minor products having cross sections similar to the observed aldehydes.
Halogen perchlorates. Reactions with fluorocarbon halides
Schack, Carl J.,Pilipovich, Don,Christe, Karl O.
, p. 145 - 151 (1975)
The reactions of chlorine perchlorate and bromine perchlorate with numerous fluoroalkyl halides were examined. In the case of fluorocarbon iodides, these reactions were generally found to produce high yields of the novel fluorocarbon perchlorates CF3
Thermal Decomposition of CF3O2NO2
Mayer-Figge, A.,Zabel, F.,Becker, K. H.
, p. 6587 - 6593 (1996)
The unimolecular decomposition rate constant of CF3O2NO2 has been measured in detail as a function of temperature, pressure, and collision partner (M = N2, O2, NO).Temperatures were between 264 and 297 K, and total pressures ranged from 3 to 1013 mbar.The first-order decay of CF3O2NO2 in the presence of excess NO was followed in a temperature-controlled DURAN glass chamber by long-path IR absorption, using the absorption bands at 1768 and 1303 cm-1.At 1013 mbar, the first-order decomposition rate constants are best represented by the Arrhenius expression k3 = 5.7E15exp-1/RT> s-1 (2?).The temperature and pressure dependencies of k3 are well reproduced by the equation log(k3/k3,infinite) = log3,0/k3,infinite)/(1 + k3,0/k3,infinite)> + log(Fc)3,0/k3,infinite)/Nc>2>-1, Nc = 0.75-1.27 log(Fc) with the parameters k3,0/ = 2.4E-5exp(-78.4 kJ mol-1/RT) cm3 molecule-1 s-1, k3,infinite = 1.49E16exp-1/RT> s-1, Fc = 0.31, and k3,0(M=O2) ca. k3,0(M=N2).By combining the present decomposition rate constants with recombination rate constants k-3 from Caralp et al., the following thermochemical data for the equilibrium CF3O2NO2 CF3O2 + NO2 (k3,k-3) are derived from second- and third-law evaluations: ΔH0r,298 = 102.7 +/- 2.0 kJ mol-1, ΔS0r,298 = 163 +/- 7 J mol-1 K-1.The temperature dependence of the equilibrium constant between 200 and 300 K is described by the expression Kc = k3/k-3 = 3.80E27exp molecules cm-3.Consistency of the data on k3 (this work) and k-3 is shown by comparing experimental and theoretical limiting low-pressure rate constants, which lead to the reasonable value βc = 0.17 for the collision efficiency of N2.The present data confirm that CF3O2NO2 is thermally quite stable in the upper troposphere and lower stratosphere and that its lifetime is probably limited by photolysis in these regions of the atmosphere.
Thermal gas-phase reaction of perfluorobuta-1,3-diene with NO2
Czarnowski, Joanna
, p. 261 - 266 (2008)
The reaction of NO2 with perfluorobuta-1,3-diene, CF2{double bond, long}CFCF{double bond, long}CF2 (C4F6), has been studied at 312.9, 323.0, 333.4, 396.0 and 418.0 K, using a conventional static system. The products formed in the temperature range 312.9-333.4 K were CF2{double bond, long}CFCF(NO2)CF2(NO2) (I), CF2(NO2)CF{double bond, long}CFCF2(NO2) (II), CF2{double bond, long}CFCF(NO2)C(O)F (III) and CF2(NO2)CF{double bond, long}CFC(O)F (IV) and FNO. The formation of these compounds was detected performing infrared and Raman spectra. The infrared spectrum shows a band at 1785 cm-1, characteristic to the terminal -CF{double bond, long}CF2 group and the Raman spectrum shows a band located at 1733 cm-1, corresponding to -CF{double bond, long}CF- group. It indicates, that in this temperature range, NO2 attacks initially only one double bound of CF2{double bond, long}CFCF{double bond, long}CF2. Since the intermediate radical CF2{double bond, long}CFC{radical dot}FCF2(NO2) formed in this process is allylic in nature, so there is no isomerization involved in this process, but rather the allylic radical is able to add the second NO2 either to CF2 or CFCF2(NO2) end, forming the corresponding products. At 396.0 and 418.0 K different products were observed: CF2(NO2)CF(NO2)C(O)F (V), NO, CF3C(O)F, C(O)F2 and traces of epoxide of tetrafluoroethene, showing that, at these temperatures, both double bonds are attacked by NO2 and detachment of CF2 group is produced. The mechanisms consistent with experimental results in the temperature range 312.9-333.4 and at 396.0 and 418 K are proposed.
Kinetics and mechanism of gas-phase reactions of n-C4F 9OCH3, i-C4F9OCH3, n-C4F9OC(O)H, and i-C4F9OC(O)H with OH radicals in an environmental reaction chamber at 253-328 K
Chen,Uchimaru,Kutsuna,Tokuhashi,Sekiya
, p. 207 - 213 (2011)
The rate constants of the reactions of n-C4F9OCH 3 (k1), i-C4F9OCH3 (k2), n-C4F9OC(O)H (k3), and i-C4F9OC(O)H (k4) with OH radicals were studied in an 11.5-dm3 environmental reaction chamber. k1 and k2 were determined to be (1.44 ± 0.33) × 10 -12 exp[-(1450 ± 70)/T] and (1.59 ± 0.41) × 10-12 exp[-(1470 ± 80)/T] cm3 molecule-1 s-1 at 253-328 K. At 298 K, k3 and k4 were deduced to be (1.71 ± 0.32) × 10-14 and (1.67 ± 0.19) × 10-14 cm3 molecule-1 s -1. The observed products of the reaction of n-C4F 9OCH3 with OH radicals were n-C4F 9OC(O)H, CF3CF2CF2C(O)F, and COF2, and those for the reaction of i-C4F 9OCH3 were i-C4F9OC(O)H, (CF 3)2CFC(O)F, CF3C(O)F, and COF2.
Atmospheric Chemistry of (CF3)2CHOCH3, (CF3)2CHOCHO, and CF3C(O)OCH3
?sterstr?m, Freja From,Wallington, Timothy J.,Sulbaek Andersen, Mads P.,Nielsen, Ole John
, p. 10540 - 10552 (2015)
Smog chambers with in situ FTIR detection were used to measure rate coefficients in 700 Torr of air and 296 ± 2 K of: k(Cl+(CF3)2CHOCH3) = (5.41 ± 1.63) × 10-12, k(Cl+(CF3)2CHOCHO) = (9.44 ± 1.81) × 10-15, k(Cl+CF3C(O)OCH3) = (6.28 ± 0.98) × 10-14, k(OH+(CF3)2CHOCH3) = (1.86 ± 0.41) × 10-13, and k(OH+(CF3)2CHOCHO) = (2.08 ± 0.63) × 10-14 cm3 molecule-1 s-1. The Cl atom initiated oxidation of (CF3)2CHOCH3 gives (CF3)2CHOCHO in a yield indistinguishable from 100%. The OH radical initiated oxidation of (CF3)2CHOCH3 gives the following products (molar yields): (CF3)2CHOCHO (76 ± 8)%, CF3C(O)OCH3 (16 ± 2)%, CF3C(O)CF3 (4 ± 1)%, and C(O)F2 (45 ± 5)%. The primary oxidation product (CF3)2CHOCHO reacts with Cl atoms to give secondary products (molar yields): CF3C(O)CF3 (67 ± 7)%, CF3C(O)OCHO (28 ± 3)%, and C(O)F2 (118 ± 12)%. CF3C(O)OCH3 reacts with Cl atoms to give: CF3C(O)OCHO (80 ± 8)% and C(O)F2 (6 ± 1)%. Atmospheric lifetimes of (CF3)2CHOCH3, (CF3)2CHOCHO, and CF3C(O)OCH3 were estimated to be 62 days, 1.5 years, and 220 days, respectively. The 100-year global warming potentials (GWPs) for (CF3)2CHOCH3, (CF3)2CHOCHO, and CF3C(O)OCH3 are estimated to be 6, 121, and 46, respectively. A comprehensive description of the atmospheric fate of (CF3)2CHOCH3 is presented.
Kinetics study of the gas-phase reactions of C2F 5OC(O)H and n-C3F7OC(O)H with OH radicals at 253-328 K
Chen,Kutsuna,Tokuhashi,Sekiya
, p. 563 - 568 (2004)
The rate constants, k1 and k2 for the reactions of C2F5OC(O)H and n-C3F7OC(O)H with OH radicals were measured using an FT-IR technique at 253-328 K. k1 and k2 were det
