Preprints
https://doi.org/10.5194/acp-2021-449
https://doi.org/10.5194/acp-2021-449

  11 Jun 2021

11 Jun 2021

Review status: this preprint is currently under review for the journal ACP.

Atmospheric oxidation of α,β-unsaturated ketones: kinetics and mechanism of the OH radical reaction

Niklas Illmann1, Rodrigo Gastón Gibilisco2, Iustinian Gabriel Bejan3, Iulia Patroescu-Klotz1, and Peter Wiesen1 Niklas Illmann et al.
  • 1Institute for Atmospheric and Environmental Research, Bergische Universität Wuppertal, 42097 Wuppertal, Germany
  • 2INQUINOA-UNT-CONICET Institute of Physical Chemistry, Faculty of Biochemistry, Chemistry and Pharmacy, National University of Tucumán, San Lorenzo 456, T4000CAN, San Miguel de Tucumán, Argentina
  • 3Faculty of Chemistry and Integrated Centre of Environmental Science Studies in the North Eastern Region Alexandru Ioan Cuza University of Iasi, 11 Carol I, Iasi 700506, Romania

Abstract. 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 cm3 molecule−1 s−1 and (8.1 ± 1.3) × 10−11 cm3 molecule−1 s−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 cm3 molecule−1 s−1 and (3.1 ± 0.4) × 10−10 cm3 molecule−1 s−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 overall organic nitrates (RONO2) yield 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.

Niklas Illmann et al.

Status: open (until 23 Jul 2021)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Niklas Illmann et al.

Niklas Illmann et al.

Viewed

Total article views: 162 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
128 32 2 162 9 1 1
  • HTML: 128
  • PDF: 32
  • XML: 2
  • Total: 162
  • Supplement: 9
  • BibTeX: 1
  • EndNote: 1
Views and downloads (calculated since 11 Jun 2021)
Cumulative views and downloads (calculated since 11 Jun 2021)

Viewed (geographical distribution)

Total article views: 162 (including HTML, PDF, and XML) Thereof 162 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 18 Jun 2021
Download
Short summary
Within this work we determined the rate coefficients and products of the reaction of unsaturated ketones with OH radicals in an effort to complete the gaps in the knowledge needed for modelling chemistry in the atmosphere. Both substances are potentially emitted by biomass burning, industrial activities or formed in the troposphere by oxidation of terpenes. As products we identified aldehydes and ketones which in turn are known to be responsible for the transportation of NOx species.
Altmetrics