EGU2020-4415, updated on 04 Apr 2023
https://doi.org/10.5194/egusphere-egu2020-4415
EGU General Assembly 2020
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Chemical composition and volatility distribution of SOA formed by ozonolysis of β-caryophyllene between 213-313 K

Linyu Gao1, Magdalena Vallon1, Junwei Song1, Wei Huang2, Thomas Leisner1, and Harald Saathoof1
Linyu Gao et al.
  • 1Karlsruhe Institute of Technology, Karlsruhe, Germany (linyu.gao@kit.edu)
  • 2University of Helsinki, Helsinki, Finland

β-Caryophyllene is the most common and abundant of the sesquiterpenes emitted into the atmosphere (Duhl et al., 2008). Although sesquiterpene emission rates were estimated to be only 9–16% of the total terpene emissions (Duhl et al., 2008), they are more reactive and larger in size than monoterpenes. Consequently, their aerosol mass yields are large and result in a significant contribution to the SOA budget in the atmosphere (Tasoglou and Pandis, 2015). Therefore, we studied the composition of both gas and particle phases as well as phase partitioning of SOA from ozonolysis of β-caryophyllene in presence and absence of NOx at five temperatures (213 K, 243 K, 273 K, 298 and 313 K) in the AIDA aerosol simulation chamber. This work focusses on the characterization of the SOA by mass spectrometry employing a FIGAERO-HR-TOF-CIMS operated with iodide ions and a HR-TOF-AMS (both Aerodyne Inc.). Particle phase analysis shows three groups of compound masses with m/z 240-400, (C5-16),  (m/z 400-560, (C20-34), and m/z 560-680, (C35-40) classified as monomers, dimers, and trimers, respectively.  Trimeric compounds were observed preferentially in SOA formed at higher temperatures (273 K, 298 K, 313 K), while only monomeric and dimeric compounds were detected at lower temperatures (243 K and 213 K). Interestingly, dimeric compounds, including CxHyOz and CxHyOzN1, contribute more to SOA mass for the lower temperatures. Comparing volatility distributions for the five different temperatures using the Volatility Basis Set (VBS) and thermal desorption information from FIGAERO-CIMS (298-473 K) we find more compounds with lower volatility for lower SOA formation temperatures. This contribution will discuss the volatility distributions obtained with and without NOx as well as the abundance of specific reaction products.

How to cite: Gao, L., Vallon, M., Song, J., Huang, W., Leisner, T., and Saathoof, H.: Chemical composition and volatility distribution of SOA formed by ozonolysis of β-caryophyllene between 213-313 K, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4415, https://doi.org/10.5194/egusphere-egu2020-4415, 2020.

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