HR: 12:06h
AN: A22C-08    [Abstracts]
TI: SOA Production From Cloud Processing of Glycolaldehyde
AU: * Perri, M J
EM: mperri@rutgers.edu
AF: Department of Environmental Sciences, Rutgers University, 14 College Farm Rd., New Brunswick, NJ 08901, United States
AU: * Perri, M J
EM: mperri@rutgers.edu
AF: Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Rd., New Brunswick, NJ 08901,
AU: Seitzinger, S P
EM: sybil@marine.rutgers.edu
AF: Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Rd., New Brunswick, NJ 08901,
AU: Seitzinger, S P
EM: sybil@marine.rutgers.edu
AF: Rutgers/NOAA CMER Program, Rutgers University, 71 Dudley Rd., New Brunswick, NJ 08901, United States
AU: Tan, Y
EM: ytan@envsci.rutgers.edu
AF: Department of Environmental Sciences, Rutgers University, 14 College Farm Rd., New Brunswick, NJ 08901, United States
AU: Turpin, B J
EM: turpin@envsci.rutgers.edu
AF: Department of Environmental Sciences, Rutgers University, 14 College Farm Rd., New Brunswick, NJ 08901, United States
AB: Recent studies suggest that aqueous cloud chemistry contributes to secondary organic aerosol (SOA) production. Gas phase primary precursors, such as ethene and isoprene, can oxidize in the interstitial spaces of clouds to form water-soluble species, including glycolaldehyde. These water-soluble products can partition into cloud droplets and undergo further oxidation (e.g., via hydroxyl radicals). If low-volatility products (e.g., oxalate) are formed, these products can remain in the particle phase following droplet evaporation, forming organic aerosol. Organic aerosol plays an important role in cloud microphysics, visibility, and human health, yet little is known about aqueous phase reaction pathways and products that contribute to SOA. The kinetics of aqueous phase glycolaldehyde oxidation were studied and products were identified. Hydroxyl radical was generated via continuous UV photolysis of hydrogen peroxide inside a glass photochemical vessel. The reaction of glycolaldehyde and hydroxyl radical was monitored in real-time via continuous electrospray ionization mass spectrometry (ESI-MS). Organic products (acids and aldehydes) formed and destroyed during the reaction were identified and quantified via negative and positive mode ionization. Based on ESI-MS data obtained, glycolaldehyde is oxidized via hydroxyl radical to glycolic acid, glyoxylic acid, and ultimately oxalic acid, as previously suggested. In addition, several unexpected higher molecular weight compounds were produced, and identification of these reaction products is currently underway. The results obtained from this study serve to validate and refine the aqueous SOA-producing pathway for glycolaldehyde in cloud chemistry models and can be used to increase the accuracy of SOA prediction in atmospheric air quality and climate models.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0317 Chemical kinetic and photochemical properties
DE: 0320 Cloud physics and chemistry
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting