Tropospheric Chemistry of CFC Replacements Hydrofluorocarbons HFCs and Hydrochlorofluorocarbons HCFCs

2 Tropospheric Chemistry of CFC Replacements Hydrofluorocarbons (HFCs) and Hydrochlorofluorocarbons (HCFCs) 

The dominant loss process for HFCs and HCFCs in the atmosphere is reaction with the OH radical. Rate constants for the OH reaction with a wide variety of HFCs and HCFCs are available (Table B.l). A mechanism for the OH reaction of the generalized HFC or HCFC species 

FIGURE 6.20 Atmospheric degradation of HFCs, HCFCs, and other CFC substitutes. Timescales for different processes are given in italics. 

There are several possible reaction paths for the haloalkoxy radicals  

Sidebottom (1995) has summarized experimental data peitaining to the fate of the haloalkoxy radicals  

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