Kinetic Studies on the Reactions of Hydroxyl Radicals with a Series of Alkoxy Esters

Abstract

Rate coefficients for the gas-phase reactions of hydroxyl radicals with a series of alkoxy esters of structure RC(O)O(CH2)nOR‘, where R = H, CH3, R‘ = CH3, C2H5, and n = 1−2, have been determined with use of relative and absolute rate methods. Relative rate measurements were performed in a Teflon reaction chamber at 298 ± 2 K and atmospheric pressure. Absolute rate measurements were made with pulsed laser photolysis−laser induced fluorescence over the temperature range 263−372 K at pressures of ∼100 Torr. The kinetic data are used to derive Arrhenius expressions for the reactions and tropospheric lifetimes for the alkoxy esters. The reactivity of the alkoxy esters is discussed in light of the current understanding of the atmospheric chemistry of oxygenated organic compounds.