Investigation of the limonene photooxidation by OH at different NO concentrations in the atmospheric simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber)

Abstract 3) was investigated in the atmospheric simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) in experiments performed at different nitric oxide (NO) mixing ratios from nearly 0 up to 10 ppbv. For the experiments dominated by OH oxidation, the formaldehyde (HCHO) yield was experimentally determined and found to be (12 ± ± ± ∼ ∼ ± ± - 1 2) concentrations by 20 % to 90 % and overestimate organic peroxyl radical (RO2) concentrations by 50 % to 300 %. The largest deviations are found in low-NO experiments and in the ozonolysis experiment. An OH radical budget analysis, which uses only measured quantities, shows that the budget is closed in most of the experiments. A similar budget analysis for RO2 radicals suggests that an additional RO2 loss rate constant of about (1–6) × - 2 - 1 2 is required to match the measured RO2 concentrations in all experiments. Sensitivity model runs indicate that additional reactions converting RO2 to HO2 at a rate constant of about (1.7–3.0) × - 2 - 1 x, HO2, 2 concentrations and OH reactivity. Reaction pathways that could lead to the production of additional OH and HO2 are discussed, which include isomerization reactions of RO2 from the oxidation of limonene, different branching ratios for the reaction of RO2 with HO2, and a faster rate constant for RO2 recombination reactions. As the exact chemical mechanisms of the additional HO2 and OH sources could not be identified, further work needs to focus on quantifying organic product species and organic peroxy radicals from limonene oxidation.

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch

References and Relationships

• Bibliographic citation: Investigation of the limonene photooxidation by OH at different NO concentrations in the atmospheric simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber) ; volume:22 ; number:13 ; year:2022 ; pages:8497-8527 ; extent:31 ; Atmospheric chemistry and physics ; 22, Heft 13 (2022), 8497-8527 (gesamt 31)

Contributors, Places and Time

• Creator: Pang, Jacky Yat Sing ; Novelli, Anna ; Kaminski, Martin ; Acir, Ismail-Hakki ; Bohn, Birger ; Carlsson, Philip ; Cho, Changmin ; Dorn, Hans-Peter ; Hofzumahaus, Andreas ; Li, Xin ; Lutz, Anna ; Nehr, Sascha ; Reimer, David ; Rohrer, Franz ; Tillmann, Ralf ; Wegener, Robert ; Kiendler-Scharr, Astrid ; Wahner, Andreas ; Fuchs, Hendrik

Further information

• DOI: 10.5194/acp-22-8497-2022
• URN: urn:nbn:de:101:1-2022070705213303323999
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 15.08.2025, 7:29 AM CEST