Keto-ether and glycol-ethers in the troposphere: reactivity toward OH radicals and Cl atoms, global lifetimes, and atmospheric implications.

Abstract

Rate coefficients for the gas-phase reactions of OH radicals and Cl atoms with 1-methoxy-2-propanone (1-M-2-PONE), 1-methoxy-2-propanol (1-M-2-POL), and 1-methoxy-2-butanol (1-M-2-BOL) were determined at room temperature and atmospheric pressure using a conventional relative-rate technique. The following absolute rate coefficients were derived: k 1(OH+1-M-2-PONE)=(0.64±0.13)×10-11, k 2(OH+1-M-2-BOL)=(2.19±0.23)×10-11, k 3(Cl+1-M-2-PONE=(1.07±0.24)×10-10, k 4(Cl+1-M-2-POL)=(2.28±0.21)×10-10, and k 5 (Cl+1-M-2-BOL)=(2.79±0.23)×10-10, in units of cm3molecule-1s-1. This is the first experimental determination of k 2-k 5. These rate coefficients were used to discuss the influence of the structure on the reactivity of the studied polyfunctional organic compounds. The atmospheric implications for 1-M-2-PONE, 1-M-2-POL, and 1-M-2-BOL and their reactions were investigated estimating atmospheric parameters such as lifetimes, global warming potentials, and average photochemical ozone production. The approximate nature of these values was stressed considering that the studied oxygenated volatile organic compounds are short-lived compounds for which the calculated parameters may vary depending on chemical composition, location, and season at the emission points.