Atmospheric chemistry of CF3CF=CF2:: Kinetics and mechanism of its reactions with OH radicals, Cl atoms, and ozone

Smog chamber/FTIR techniques were used to study the OH radical, the Cl atom, and ozone initiated oxidation of CF3CF=CF2 in 700 Torr of air at 296 K. Relative rate methods were used to measure k(OH + CF3CF= CF2) = (2.4 +/- 0.3) x 10(-12) and k(Cl + CF3CF=CF2) = (2.7 +/- 0.3) x 10(-11); absolute techniques were used to derive an upper limit of k(O-3 + CF3CF=CF2) < 3 x 10(-21) cm(3) molecule(-1) s(-1). OH radical and Cl atominitiated atmospheric oxidation of CF3CF=CF2 gives COF2 and CF3C(O)F in molar yields of 100%. The atmospheric lifetime of CF3CF=CF2 is approximately 9 days with degradation proceeding via reaction with OH radicals to give trifluoroacetic acid in a molar yield of 100%. Results are discussed with respect to previous measurements of k(OH + CF3CF=CF2) and k(O-3 + CF3CF=CF2) and the potential importance of CF3CF=CF2 as a source of trifluoroacetic acid.