PRODUCTS AND MECHANISMS OF THE REACTIONS OF A SERIES OF HYDROFLUOROALKENES INITIATED BY OH RADICALS

M. TERUEL , C. RIVELA, RODRIGO. G. GIBILISCO, M.B. BLANCO, I. BARNES, P. WIESEN

Lille

Simposio; The 25 th International Symposium on Gas Kinetics and Related Phenomena; 2018

Gas Kinetic group-RSC

Fluorinated compounds are environmentally persistent and have been demonstrated to bioaccumulate and contribute to climate change1. As a result, alternatives are being proposed fluorinated compounds that have lower atmospheric lifetimes and Global Warming Potential (GWP), which include the hydrofluorinated alkenes2. Within hydrofluoroalkenes (HFAs), 2-fluoropropene (2-FP), (E/Z)-isomeric mixture of 1,2,3,3,3-pentafluoropropene (PFP) and 3,3,3-trifluoro-2-(trifluoromethyl) propene (HXFP) are widely use in industrial applications as alternatives refrigerants; in pharmaceutical uses and production of perfluorinated polymers 3. In this work we have studied the atmospheric degradation pathways of the reaction of HFAs with OH radicals:OH + CH3CF=CH2 → Products (1)OH + (CF3)2C=CH2→ Products (2)OH + (E/Z)-CF3CF=CHF→ Products (3)The following reaction products have been identified and quantified:CH3C(O)F, HC(O)H (1), CF3C(O)CF3, HC(O)H (2) and CF3C(O)F, FC(O)H (3).The experiments were performed at 1000 mbar of synthetic air using an atmospheric simulation chamber of 480 L capacity. The products mentioned above are the majority products of these reactions. The result indicates that the products proceed of the alcoxy intermediated of the reactions of OH radicals with HFAs by initial addition of OH to the ˃C=C˂ bond.The results will contribute to an improved representation of the degradation of fluorinated alkenes in the atmospheric chemical models used to assess the environmental impact of chemicals and their contribution to the oxidizing capacity of the atmosphere.References1. https://www.basf.com.2. Blanco MB, Teruel MA. Photodegradation of butyl acrylate in the troposphere by OH radicals: kinetics and fate of 1, 2-hydroxyalcoxy radicals. J Phys Org Chem. 2008;21(5):397-401.3. Lindley AA, Noakes TJ. Consideration of Hydrofluoroolefins (HFOs) as potential candidate medical propellants. Mex Fluor on-line Publ (www Mex com). 2010.