Title: | Insights into secondary organic aerosol formation mechanisms from measured gas/particle partitioning of specific organic tracer compounds |
Author(s): | Zhao Y; Kreisberg NM; Worton DR; Isaacman G; Weber RJ; Liu S; Day DA; Russell LM; Markovic MZ; VandenBoer TC; Murphy JG; Hering SV; Goldstein AH; |
Address: | "Department of Environmental Science, Policy and Management, University of California, Berkeley, California, USA" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "In situ measurements of organic compounds in both gas and particle phases were made with a thermal desorption aerosol gas chromatography (TAG) instrument. The gas/particle partitioning of phthalic acid, pinonaldehyde, and 6,10,14-trimethyl-2-pentadecanone is discussed in detail to explore secondary organic aerosol (SOA) formation mechanisms. Measured fractions in the particle phase (f(part)) of 6,10,14-trimethyl-2-pentadecanone were similar to those expected from the absorptive gas/particle partitioning theory, suggesting that its partitioning is dominated by absorption processes. However, f(part) of phthalic acid and pinonaldehyde were substantially higher than predicted. The formation of low-volatility products from reactions of phthalic acid with ammonia is proposed as one possible mechanism to explain the high f(part) of phthalic acid. The observations of particle-phase pinonaldehyde when inorganic acids were fully neutralized indicate that inorganic acids are not required for the occurrence of reactive uptake of pinonaldehyde on particles. The observed relationship between f(part) of pinonaldehyde and relative humidity suggests that the aerosol water plays a significant role in the formation of particle-phase pinonaldehyde. Our results clearly show it is necessary to include multiple gas/particle partitioning pathways in models to predict SOA and multiple SOA tracers in source apportionment models to reconstruct SOA" |
Keywords: | "Aerosols/*analysis Aldehydes Anions/analysis Carbon/analysis Cations/analysis Chromatography, Gas Cyclobutanes Gases/*analysis Ketones/analysis Organic Chemicals/*analysis Oxygen/analysis Particulate Matter/*analysis Phthalic Acids Time Factors Vapor Pres;" |
Notes: | "MedlineZhao, Yunliang Kreisberg, Nathan M Worton, David R Isaacman, Gabriel Weber, Robin J Liu, Shang Day, Douglas A Russell, Lynn M Markovic, Milos Z VandenBoer, Trevor C Murphy, Jennifer G Hering, Susanne V Goldstein, Allen H eng Research Support, Non-U.S. Gov't 2013/03/02 Environ Sci Technol. 2013 Apr 16; 47(8):3781-7. doi: 10.1021/es304587x. Epub 2013 Mar 27" |