Rate Coefficient for the Gas-Phase OH + CHF=CF2 Reaction between 212 and 375 K

(2016), Rate Coefficient for the Gas-Phase OH + CHF=CF2 Reaction between 212 and 375 K.

Rate coefficients, k(T), for the OH + CHF=CF2 (trifluoroethylene, HFO-1123) gasphase reaction were measured under pseudo–first-order conditions using pulsed laser photolysis to produce OH radicals and pulsed laser induced fluorescence to measure the OH radical temporal profile. Rate coefficients were measured over the temperature range 212–375 K at total pressures between 20 and 500 Torr (He, N2 bath gas). The rate coefficient was found to be independent of pressure over this range of pressure with a temperature dependence that is described by the Arrhenius expression (3.04 ± 0.30) × 10–12 exp[(312 ± 25)/T] cm3 molecule–1 s–1 with k(296 K) measured to be (8.77 ± 0.80) × 10–12 cm3 molecule–1 s–1 (quoted uncertainties are 2σ and include estimated systematic errors). Rate coefficients for the reaction of CHF=CF2 with 18 OH and OD were also measured as part of this study at 296 and 373 K and a total pressure of 25 Torr (He). The isotope measurements were used to evaluate the observed OH radical regeneration. CHF=CF2 is a very short-lived substance with an atmospheric lifetime of 1 day with respect to OH reactive loss, whereas the actual lifetime of CHF=CF2 will depend on the time and location of its emission. The global warming potential for CHF=CF2 on the 100-year time horizon (GWP100 ) was estimated using the present results and a lifetime correction factor to be 3.9 × 10−3 . 

C 2016 Wiley Periodicals, Inc. Int J Chem Kinet 48: 714–723, 2016

Research Program: 
Upper Atmosphere Research Program (UARP)