EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Impact of NOx in SOA and organonitrates production

Eleonora Aruffo1,2, Junfeng Wang3, Jianhuai Ye4, Paul Ohno5, Yiming Qin6, Matthew Stewart5, Karena McKinney7, Piero Di Carlo1,2, and Scot T. Martin5,8
Eleonora Aruffo et al.
  • 1Department of Advanced Technologies in Medicine & Dentistry, University "G. d'Annunzio" of Chieti-Pescara, Chieti, Italy
  • 2Center for Advanced Studies and Technology-CAST, Chieti, Italy
  • 3Jiangsu Key Laboratory of Atmospheric Environment Monitoring and pollution control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Sci
  • 4School of Environmental Science & Engineering, Southern University of Science and Technology, Shenzhen, China
  • 5School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA
  • 6Department of Chemistry, University of California Irvine, Irvine, California, USA
  • 7Department of Chemistry, Colby College, Waterville, USA,
  • 8Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts, USA

The concentration of nitrogen oxides (NOx) and their reservoir species, the organonitrates (ON), impacts on the secondary organic aerosol (SOA) production. To estimate the effect of different NOx levels on SOA, we carried out a series of laboratory experiments at the Harvard Environmental Chamber (HEC) investigating the production and partitioning of total organonitrates from α-pinene photo-oxidation in a NOx range varying between 1 ppb and 24 ppb. We measured not only the aerosol mass concentration by using a Scanning Mobility Particle Sizer (SMPS) and composition by an on-line aerosol mass spectrometry (AMS), but also the gas phase and particle-phase organonitrates (gON and pON, respectively) by a thermal dissociation laser-induced fluorescence (TDLIF). In our experimental conditions, we found the presence of crossover point of 6 ppb of NOx between clean and polluted conditions that affect the SOA production: in fact, the SOA yield for 1 to 6 ppb NOx increased, and for >6 ppb NOx steadily dropped. The ON partitioning ratio (pON/(pON+gON)) has been estimated, identifying that also this ratio is strongly affected by the NOx concentrations; in fact, it decreased from 0.27 to 0.13 as the NOx increased from <1 to 24 ppb. 

How to cite: Aruffo, E., Wang, J., Ye, J., Ohno, P., Qin, Y., Stewart, M., McKinney, K., Di Carlo, P., and Martin, S. T.: Impact of NOx in SOA and organonitrates production, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12952,, 2022.