Kinetic study of the atmospheric oxidation of a series of epoxy compounds by OH radicals

Abstract. In this work, we study the kinetics of gas-phase reactions hydroxyl radicals with cyclohexene oxide (CHO), 1,2-epoxyhexane (EHX), 1,2-epoxybutane (12EB), trans-2,3-epoxybutane (tEB) and cis-2,3-epoxybutane (cEB) using relative rate technique. The experiments were conducted at (298 ± 3) K (760 10) Torr ((1.01 0.01) × 105 Pa) total pressure synthetic air different reference compounds in a 1080 L Quartz Reactor (QUAREC) 480 Duran glass chamber. following room temperature coefficients (cm3 molecule?1 s?1) obtained: k1(OH+CHO)=(5.93±1.13)×10-12, k2(OH+EHX)=(5.77±0.83)×10-12, k3(OH+12EB)=(1.98±0.29)×10-12, k4(OH+cEB)=(1.50±0.28)×10-12 k5(OH+tEB)=(1.81±0.33)×10-12. Except for previous studies on oxide, is, to best our knowledge, first kinetic reaction these OH radicals. We discuss discrepancies found between values obtained from present estimated structure–activity relationship method (SAR). Our findings indicate that pseudo-ethylenic character epoxy ring is an important factor be included improvement SAR estimation method. Atmospheric lifetimes, reactivity trends atmospheric implications are discussed considering compound study.