Kinetic studies of OH reactions with propylal, butylal and 1,3-dioxolane
Abstract
Rate coefficients have been measured for the gas phase reactions of hydroxyl (OH) radicals with three acetals, di-n-propoxymethane (n-C3H7OCH2On-C3H7), di-n-butoxymethane (n-C4H9OCH2On-C4H9) and 1,3-dioxolane. The experiments were carried out using the pulsed laser photolysis - laser induced fluorescence technique over the temperature range 243–372 K and the kinetic data were used to derive the following Arrhenius expressions (in units of cm3 molecule−1 s−1): di-n-propoxymethane, k1 = (4.39 ± 1.06) × 10−12 exp[(563 ± 74)/T]; di-n-butoxymethane, k2 = (5.15 ± 0.66) × 10−12 exp[(590 ± 38)/T]; and 1,3-dioxolane, k3 = (6.70 ± 0.86) × 10−12 exp[(154 ± 36)/T]. At 298 K, the rate coefficients obtained (in units of 10−12 cm3 molecule−1 s−1) are: k1 = (27.6 ± 2.3), k2 = (37.0 ± 5.2) and k3 = (11.1 ± 0.9). The results are discussed in terms of structure–activity relationships and used to derive atmospheric lifetimes for these acetals.