HR: 14:55h
AN: A33C-04 INVITED     [Abstracts]
TI: Heterogeneous oxidation and photochemistry of PAHs
AU: * Donaldson, D
EM: jdonalds@chem.utoronto.ca
AF: Department of Chemistry University of Toronto, 80 St George St , Toronto, ON M5S 3H6, Canada
AU: Kahan, T F
EM: tkahan@chem.utoronto.ca
AF: Department of Chemistry University of Toronto, 80 St George St , Toronto, ON M5S 3H6, Canada
AU: Kwamena, N A
EM: nkwamena@chem.utoronto.ca
AF: Department of Chemistry University of Toronto, 80 St George St , Toronto, ON M5S 3H6, Canada
AB: Until recently, the atmospheric degradation of polycyclic aromatic hydrocarbons (PAHs) was thought to occur primarily via gas phase reaction with OH or NO3. We have measured the heterogeneous oxidation kinetics of naphthalene, anthracene, fluoranthene, phenanthrene, pyrene, and benzo[a]pyrene sorbed on an "urban grime" substrate with gas phase ozone over a wide range of ozone concentrations. Including these kinetics in mass- balance models shows that they may be very important in establishing the fate of PAHs in urban environments. The photolysis rates of anthracene and naphthalene at the air-ice interface were measured, and the kinetics were compared to those observed in water solution and at the air-water interface. Reaction at the ice surface is 4-6 X faster than at the water surface, probably due to an enhancement in the absorption cross sections and/or photolysis quantum yields.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0317 Chemical kinetic and photochemical properties
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly