A theoretical study on gas-phase reactions of Acrolein with NO 3 : mechanism, kinetics and insights

Abstract

Abstract The explicit reaction mechanism and dynamics of acrolein (CH2 = CHCHO) with NO3 were researched. NO3 might add to the carbon atom of C = C double bond of CH2 = CHCHO to generate IM1 (CH2ONO2CHCHO) and IM2 (CH2CHONO2CHO), and IM1 and IM2 could mutual transformation. Moreover, IM1 and IM2 could also generate a five-membered ring adducts (IM3), and then generate corresponding products. In addition, NO3 could abstract the H atom of acrolein, and the most pathway is abstracted the H atom of the -CHO group to generate h-P3 (CH2CHCO + HNO3). The H-abstraction reactions are more feasible than the addition reaction in energy. The subsequent reactions of IM1 (CH2ONO2CHCHO), IM2 (CH2CHONO2CHO) and h-P3 were detailed investigated. The computed total rate constant increase with the temperature raising from 200–3000 K, and the rate constant is 1.43 ×10− 15 cm3 molecule− 1 s− 1 at 298 K, which is consistent with the experimental values. The lifetime of Acrolein oxidized by NO3 radicals is estimated to be 14.20 days. Our theoretical investigations are of significant in understanding the oxidation process of unsaturated aldehyde by NO3.