Product distribution and mechanism of the OH − initiated tropospheric degradation of three CFC replacement candidates: CH 3 CFCH 2 , (CF 3 ) 2 CCH 2 and ( E / Z )-CF 3 CFCHF

RIVELA, CYNTHIA B.; TOVAR, CARMEN M.; GIBILISCO, RODRIGO; TERUEL, MARIANO A.; BARNES, IAN; WIESEN, PETER; BLANCO, MARÍA B.

RSC Advances

The Royal Society of Chemistry

Lugar: Londres; Año: 2019 vol. 9 p. 5592 - 5598

The OH radical initiated photodegradation of 2-fluoropropene (CH3CF]CH2), 3,3,3-trifluoro-2-(tri-fluoromethyl)propene ((CF3)2C]CH2) and (E/Z)-1,2,3,3,3 pentafluoropropene ((E/Z)-CF3CF]CHF) has been investigated for the first time using a 1080 L quartz-glass environmental chamber at 298 2 K and atmospheric pressure of synthetic air coupled with in situ FTIR spectroscopy to monitor reactants and products. The major products observed in the OH reaction were CH3C(O)F (98 5)% together with HC(O)H (89 7)% as a co-product, CF3C(O)F (103 8)% together with HC(O)F (96 7)% as a co- product and CF3C(O)CF3 (91 8)% together with HC(O)H (98 12)% as a co-product from the C1?C2 bond cleavage channel of the intermediate hydroxyalkoxy radical, formed by addition of OH to the terminal carbon of the double bond which is designated C1 of 2 fluoropropene, (E/Z)-1,2,3,3,3- pentafluoropropene and 3,3,3-trifluoro-2-(tri-fluoromethyl)propene, respectively. The present results arecompared with previous studies for the reaction of OH with the separate isomers (E) and (Z) of 1,2,3,3,3-pentafluoropropene. In addition, atmospheric implications of the reactions studied are discussed.