Journal of Atmospheric Chemistry

, Volume 16, Issue 4, pp 301–312 | Cite as

Tropospheric degradation products of CH2FCF3 (HFC-134a)

  • Ernesto C. Tuazon
  • Roger Atkinson
Article

Abstract

Chlorine atom-initiated photooxidations of CH2FCF3 (HFC-134a) in O2-N2 diluent were carried out to identify the products formed from the\(CF_3 CHF\dot O\) radical reactions and to determine the product yields as a function of temperature, pressure and O2 concentration. CF3C(O)F and HC(O)F were the major ‘first-generation’ products observed, along with smaller yields of C(O)F2 and, as yet, undetermined yields of CF3OOOCF3 and CF3OOC(O)F. The relative importance of the two major\(CF_3 CHF\dot O\) reaction pathways,
is expressed by the rate constant ratio
$$k_{O_2 } /k_d = 3.2 \times 10^{ - 25} e^{(3510 \pm 470)/T} cm^3 molecule^{ - 1}$$
The decomposition reaction leading to HC(O)F and ĊF3 radical products is predicted to be the dominant pathway at the Earth's surface while mainly CF3C(O)F formation will occur at the tropopause.

Key words

1,1,1,2-tetrafluoroethane (HFC-134a) products troposphere 

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Copyright information

© Kluwer Academic Publishers 1993

Authors and Affiliations

  • Ernesto C. Tuazon
    • 1
  • Roger Atkinson
    • 1
  1. 1.Statewide Air Pollution Research CenterUniversity of CaliforniaRiversideUSA

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