Presentation Title
Secondary Organic Aerosol Production via Ozonolysis of Green Leaf Volatiles
Abstract
Aerosols are ubiquitous in the atmosphere and play important roles in environmental processes. Secondary organic aerosols (SOA) in particular are produced via gas phase oxidation reactions of volatile organic compounds (VOCs). Recently, focus has shifted to green leaf volatiles (GLVs; a subset of VOCs), which have the potential to contribute significantly to the overall SOA budget. Here, investigations of the ozonolysis of relevant GLV SOA precursors cis-3-hexenyl acetate (CHA) and cis-3-hexenol (HXL) are presented. Specifically, a Scanning Mobility Particle Sizer (SMPS), Electrical Low Pressure Impactor (ELPI), and Near-Infrared Laser Desorption-Ionization Aerosol Mass Spectrometer (NIR-LDI-AMS) were utilized to probe both physical and chemical properties of SOA formed in the University of Vermont Environmental Chamber (UVMEC) under dry (relative humidity, RH <2%) and humid (82%< RH <90%) conditions. Results suggest the presence of oxidation pathways allowing for the production of highly oxygenated SOA products in addition to prominent oligomers, both exhibiting partial non-liquid characteristics. In contrast to the CHA and HXL derived SOA produced under dry conditions, SOA produced under high RH conditions exhibited larger particle diameters, lower mass loadings, and increased prevalence of lower molecular weight products, while the relative phase remained similar. These findings have important implications for the distribution, abundance, and transport of atmospheric gases, as well as Earth’s radiative budget via light scattering, light absorbance, and cloud formation.
Primary Faculty Mentor Name
Giuseppe Petrucci
Faculty/Staff Collaborators
Christopher Snyder
Status
Graduate
Student College
College of Arts and Sciences
Program/Major
Chemistry
Primary Research Category
Engineering & Physical Sciences
Secondary Organic Aerosol Production via Ozonolysis of Green Leaf Volatiles
Aerosols are ubiquitous in the atmosphere and play important roles in environmental processes. Secondary organic aerosols (SOA) in particular are produced via gas phase oxidation reactions of volatile organic compounds (VOCs). Recently, focus has shifted to green leaf volatiles (GLVs; a subset of VOCs), which have the potential to contribute significantly to the overall SOA budget. Here, investigations of the ozonolysis of relevant GLV SOA precursors cis-3-hexenyl acetate (CHA) and cis-3-hexenol (HXL) are presented. Specifically, a Scanning Mobility Particle Sizer (SMPS), Electrical Low Pressure Impactor (ELPI), and Near-Infrared Laser Desorption-Ionization Aerosol Mass Spectrometer (NIR-LDI-AMS) were utilized to probe both physical and chemical properties of SOA formed in the University of Vermont Environmental Chamber (UVMEC) under dry (relative humidity, RH <2%) and humid (82%< RH <90%) conditions. Results suggest the presence of oxidation pathways allowing for the production of highly oxygenated SOA products in addition to prominent oligomers, both exhibiting partial non-liquid characteristics. In contrast to the CHA and HXL derived SOA produced under dry conditions, SOA produced under high RH conditions exhibited larger particle diameters, lower mass loadings, and increased prevalence of lower molecular weight products, while the relative phase remained similar. These findings have important implications for the distribution, abundance, and transport of atmospheric gases, as well as Earth’s radiative budget via light scattering, light absorbance, and cloud formation.