Journal of Physical Chemistry A, Vol.105, No.48, 10854-10859, 2001
Kinetics and mechanisms for the reactions of CF3OCH3 and CF3OC(O)H with OH radicals using an environmental reaction chamber
The atmospheric chemistry of CF3OCH3, a possible HCFCs/HFCs substitute was studied using a smog chamber/FTIR technique. The ether was reacted with OH radicals prepared by photolysis of ozone in 100 Torr of an H2O/O-2/He gas mixture in a 1 m(3) temperature-controlled chamber. Using a relative rate method, k(OH + CF3OCH3) = (4.22 +/- 0.84) x 10(-12) exp[(-1750 +/-350)/T] cm(3) molecule(-1) s(-1) over the temperature range 268-308 K. The rate constant at 298 K was (1.19 +/- 0.14) x 10(-14) cm(3) molecule(-1) s(-1). The products of the OH radical initiated degradation of CF3OCH3 were investigated in 100-230 Torr of an O-2/He gas mixture at 298 K using in situ FTIR spectroscopy. k(OH + CF3OC(O)H) = (1.68 +/- 0.20) x 10(-14) cm(3) molecule(-1) s(-1) at 298 K was determined. The major products of the oxidation of CF3OC(O)H were COF2 and CO2. These results are discussed with respect to the atmospheric chemistry of CF3OCH3 and CF3OC(O)H.