AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
What Aerosol Water do Organic Compounds See?
HAVALA PYE, Andreas Zuend, Jin Ma, Shannon Capps, Gabriel Isaacman-VanWertz, Juliane L. Fry, Lu Xu, Nga Lee Ng, Allen H. Goldstein, Environmental Protection Agency
Abstract Number: 346 Working Group: There Must be Something in the Water: Cloud, Fog and Aerosol Aqueous Chemistry for Aerosol Production
Abstract Large amounts of aerosol water are associated with inorganic salts such as ammonium sulfate with generally smaller but important contributions from hydrophilic organics. Ambient aerosols can be externally or internally mixed in addition to containing one or multiple phases. The degree to which organic compounds in a particle interact with water associated with inorganic salts will influence their partitioning between the gas and aerosol phase as well as opportunity to participate in aqueous chemistry. In this work, we examine the potential for liquid-liquid phase separation, or lack thereof, within PM2.5 particles to affect the partitioning of compounds between the gas and aerosol phases. We examine partitioning of ammonia and several isoprene- and monoterpene-derived organic compounds using common (absorptive partitioning, ISORROPIA) and advanced (AIOMFAC) approaches to describing gas-aerosol partitioning for conditions during the Southern Oxidant and Aerosol Study (SOAS). We aim to address the degree to which sophisticated techniques accounting for organic-inorganic interactions, deviations in ideality, and phase separation reproduce observations and the information gained or still needed to further their usefulness.