AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Utilizing Outdoor Chambers to Quantify Secondary Organic Aerosol Formation from Evaporative Emissions of Commercial Fuels and Aromatics
TERRY LATHEM, Jeff Bean, Shaokai Gao, John Gingerich, Phillips 66
Abstract Number: 297 Working Group: Aerosol Chemistry
Abstract A large fraction of ambient particulate matter (PM) is comprised of secondary organic aerosol (SOA), which is formed in the atmosphere through oxidation of natural and anthropogenic volatile organic compounds (VOCs). To ensure cost effective and efficient regulatory compliance for PM, detailed understanding of the formation and evolution of SOA is required. Photochemical models, such as the Community Multi-scale Air Quality Model (CMAQ) and Comprehensive Air Quality Model with Extensions (CAMx), are continuously being advanced to predict SOA yields. However, these models are still challenged with accurately representing the SOA measured in the atmosphere for the wide range of ambient conditions observed.
This presentation will discuss the current challenges and uncertainties in quantifying and measuring SOA originating from commercial fuel sources, with an emphasis on measuring and modeling the SOA formation observed under real-world conditions. Outdoor chamber experiments using sunlight were used to quantify the SOA formation from the photo-oxidation of evaporative emissions of fuels and aromatics under varying environmental conditions. The outdoor chamber experiments were simulated with the SAPRC box model, utilizing the SAPRC-07 gas-phase chemical mechanism and the AERO6 SOA mechanism. Comparison of measured vs. model predicted SOA yields will be presented and the impact of varying environmental conditions will be discussed.