INVESTIGADORES
GIBILISCO Rodrigo Gaston
artículos
Título:
Atmospheric oxidation of α,β-unsaturated ketones: kinetics and mechanism of the OH radical reaction
Autor/es:
ILLMANN NIKLAS ; GIBILISCO RODRIGO GASTÓN; BEJAN IUSTINIAN GABRIEL; PATROESCU-KLOTZ IULIA; WIESEN PETER
Revista:
ATMOSPHERIC CHEMISTRY AND PHYSICS
Editorial:
COPERNICUS PUBLICATIONS
Referencias:
Lugar: Gottingen; Año: 2021
ISSN:
1680-7316
Resumen:
The OH-radical-initiated oxidation of 3-methyl-3-penten-2-one and 4-methyl-3-penten-2-one was investigated in two atmospheric simulation chambers at 298±3 K and 990±15 mbar using long-path FTIR spectroscopy. The rate coefficients of the reactions of 3-methyl-3-penten-2-one and 4-methyl-3-penten-2-one with OH radicals were determined to be (6.5±1.2)×10−11 and (8.1±1.3)×10−11 cm3molecule−1s−1, respectively. To enlarge the kinetics data pool the rate coefficients of the target species with Cl atoms were determined to be (2.8±0.4)×10−10 and (3.1±0.4)×10−10 cm3molecule−1s−1, respectively. The mechanistic investigation of the OH-initiated oxidation focuses on the RO2+NO reaction. The quantified products were acetoin, acetaldehyde, biacetyl, CO2 and peroxyacetyl nitrate (PAN) for the reaction of 3-methyl-3-penten-2-one with OH radicals and acetone, methyl glyoxal, 2-hydroxy-2-methylpropanal, CO2 and peroxyacetyl nitrate (PAN) for the reaction of 4-methyl-3-penten-2-one with OH, respectively. Based on the calculated product yields an upper limit of 0.15 was determined for the yield of RONO2 derived from the OH reaction of 4-methyl-3-penten-2-one. By contrast, no RONO2 formation was observed for the OH reaction of 3-methyl-3-penten-2-one. Additionally, a simple model is presented to correct product yields for secondary processes.