Room Temperature Kinetics of the Reaction of OH with Ethylene Oxide
Abstract
The gas-phase oxidation of ethylene oxide (EtO, C 2 H 4 O) by the hydroxyl radical (OH) is the primary atmospheric pathway for removing this known carcinogen from the troposphere. The rate coefficient of the OH + EtO reaction was measured at room temperature (296 K) in a temperature- and pressure-controlled reactor using pulsed laser photolysis–laser-induced fluorescence (PLP–LIF). Time-resolved pseudo-first order OH decays, generated by photolyzing H 2 O 2, HNO 3, or (CH 3 ) 3 COOH at 248 nm, were measured using LIF in EtO/N 2 mixtures at total pressures of 67 and 267 hPa. The observed rate coefficient, k 1 (296 K) = (1.09 ± 0.10) × 10 –13 cm 3 molecule –1 s –1, is approximately 25% faster than the current recommended value. These results are compared with previous room-temperature studies, and atmospheric lifetimes of EtO with respect to OH are discussed.
Fields of Study & Subjects
Atmospheric chemistry and aerosols
Air Quality and Health Impacts
Atmospheric Ozone and Climate
Publication details
- Journal / source
- The Journal of Physical Chemistry Letters
- Publisher
- American Chemical Society (ACS)
- Volume
- 17
- Issue
- 2
- Pages
- 635–639
- Publication date
- 6 January 2026
- Language
- EN