Kinetic study of the reaction of the CFCl{sub 2}CH{sub 2}O radical with O{sub 2}
- Univ. of Minnesota, Minneapolis, MN (United States)
The 2-fluoro-2,2-dichloroethoxy radical, CFCl{sub 2}CH{sub 2}O, is an intermediate in the mechanism of the tropospheric degradation of CFCl{sub 2}CH{sub 3} (HCFC-141b), a chlorofluoromethane replacement in some large-scale industrial applications. In this work, the reaction of CFCl{sub 2}CH{sub 2}O with O{sub 2} was investigated at 10-35 Torr and 251-341 K by UV flash photolysis and time-resolved mass spectrometry. CFCl{sub 2}CH{sub 2}O{sub 2} radicals were formed from the photolysis of CFCl{sub 2}CH{sub 3}/N{sub 2}/O{sub 2} mixtures. The CFCl{sub 2}CH{sub 2}O radical is a product of the reactions of CFCl{sub 2}CH{sub 2}O{sub 2} with Cl and ClO and the self-reaction. The rate of formation and decay of CFCl{sub 2}CH{sub 2}O was followed by observations of the fragment ion CClCH{sub 2}O{sup +}. The rate coefficient of the reaction of CFCl{sub 2}CH{sub 2}O with O{sub 2}, determined from CHCl{sub 2}CH{sub 2}O decay in excess O{sub 2} by both pseudo-first-order analysis and nonlinear regression, can be expressed as (2.4{+-}0.5) x 10{sup -15} exp[-(944{+-}55)/T] cm{sup 3} molecule{sup -1} s{sup -1}. The half-life for removal of CFCl{sub 2}CH{sub 2}O radicals from the atmosphere by the title reaction is 6 ms in the mid-troposphere and 1 s in the mid-stratosphere. 43 refs., 6 figs., 5 tabs.
- OSTI ID:
- 263181
- Journal Information:
- Journal of Physical Chemistry, Vol. 100, Issue 22; Other Information: PBD: 30 May 1996
- Country of Publication:
- United States
- Language:
- English
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