Atmospheric chemistry of (CF3)2CF-C ≡ N

Abstract

FTIR/smog chamber experiments and ab initio quantum calculations were performed to investigate the atmospheric chemistry of (CF3)2CFCN, a proposed replacement compound for the industrially important sulfur hexafluoride, SF6. The present study determined k(Cl+(CF3)2CFCN) = (2.33 ± 0.87) × 10–17, k(OH + (CF3)2CFCN) = (1.45 ± 0.25) × 10− 15 and k(O3 + (CF3)2CFCN) ≤ 6 × 10− 24 cm3 molecule–1 s–1, respectively. The experiments were performed in 700 Torr of N2 or air diluent at 296 ± 1 K. The main atmospheric sink for (CF3)2CFCN was determined to be the reaction with OH radicals. In assessing the atmospheric impact of (CF3)2CFCN, an infrared spectrum was recorded, and the atmospheric lifetime, the radiative forcing, and the global warming potential (GWP) were calculated. The integrated cross section (650–1500 cm− 1) for (CF3)2CFCN is (2.22 ± 0.11) × 10− 16 cm2 molecule− 1 cm− 1 which results in a radiative efficiency of 0.217 W m− 2 ppb− 1. The 100-year Global Warming Potential (GWP) for (CF3)2CFCN was calculated to be 1490. The climate impact of (CF3)2CFCN is significantly lower than that of SF6. This study provides a comprehensive description of the atmospheric fate of (CF3)2CFCN.