Title: | Volatility of Secondary Organic Aerosol from beta-Caryophyllene Ozonolysis over a Wide Tropospheric Temperature Range |
Author(s): | Gao L; Buchholz A; Li Z; Song J; Vallon M; Jiang F; Mohler O; Leisner T; Saathoff H; |
Address: | "Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe 76344, Germany. Institute of Geography and Geoecology, Working Group for Environmental Mineralogy and Environmental System Analysis, Karlsruhe Institute of Technology, Karlsruhe 76131, Germany. Department of Technical Physics, University of Eastern Finland, Kuopio 70210, Finland. International Laboratory for Air Quality and Health, School of Earth and Atmospheric Sciences, Queensland University of Technology, Brisbane, QLD 4001, Australia. Institute of Environmental Physics, Heidelberg University, Heidelberg 69120, Germany" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Print) 0013-936X (Linking) |
Abstract: | "We investigated secondary organic aerosol (SOA) from beta-caryophyllene oxidation generated over a wide tropospheric temperature range (213-313 K) from ozonolysis. Positive matrix factorization (PMF) was used to deconvolute the desorption data (thermograms) of SOA products detected by a chemical ionization mass spectrometer (FIGAERO-CIMS). A nonmonotonic dependence of particle volatility (saturation concentration at 298 K, C(298K)(*)) on formation temperature (213-313 K) was observed, primarily due to temperature-dependent formation pathways of beta-caryophyllene oxidation products. The PMF analysis grouped detected ions into 11 compound groups (factors) with characteristic volatility. These compound groups act as indicators for the underlying SOA formation mechanisms. Their different temperature responses revealed that the relevant chemical pathways (e.g., autoxidation, oligomer formation, and isomer formation) had distinct optimal temperatures between 213 and 313 K, significantly beyond the effect of temperature-dependent partitioning. Furthermore, PMF-resolved volatility groups were compared with volatility basis set (VBS) distributions based on different vapor pressure estimation methods. The variation of the volatilities predicted by different methods is affected by highly oxygenated molecules, isomers, and thermal decomposition of oligomers with long carbon chains. This work distinguishes multiple isomers and identifies compound groups of varying volatilities, providing new insights into the temperature-dependent formation mechanisms of beta-caryophyllene-derived SOA particles" |
Keywords: | Temperature *Air Pollutants/analysis Aerosols/analysis *Ozone/analysis positive matrix factorization (PMF) secondary organic aerosol (SOA) temperature dependence volatility beta-caryophyllene; |
Notes: | "MedlineGao, Linyu Buchholz, Angela Li, Zijun Song, Junwei Vallon, Magdalena Jiang, Feng Mohler, Ottmar Leisner, Thomas Saathoff, Harald eng Research Support, Non-U.S. Gov't 2023/06/08 Environ Sci Technol. 2023 Jun 20; 57(24):8965-8974. doi: 10.1021/acs.est.3c01151. Epub 2023 Jun 7" |