Heterogeneous oxidation kinetics of organic biomass burning aerosol surrogates by O(3), NO(2), N(2)O(5), and NO(3)

Knopf, DA; Forrester, SM; Slade, JH

HERO ID

862656

Reference Type

Journal Article

Year

2011

Language

English

PMID

22020363

HERO ID 862656
In Press No
Year 2011
Title Heterogeneous oxidation kinetics of organic biomass burning aerosol surrogates by O(3), NO(2), N(2)O(5), and NO(3)
Authors Knopf, DA; Forrester, SM; Slade, JH
Journal Physical Chemistry Chemical Physics
Volume 13
Issue 47
Page Numbers 21050-21062
Abstract The reactive uptake coefficients (γ) of O(3), NO(2), N(2)O(5), and NO(3) by levoglucosan, abietic acid, nitroguaiacol, and an atmospherically relevant mixture of those species serving as surrogates for biomass burning aerosol have been determined employing a chemical ionization mass spectrometer coupled to a rotating-wall flow-tube reactor. γ of O(3), NO(2), N(2)O(5), and NO(3) in the presence of O(2) are in the range of 1-8 × 10(-5), <10(-6)-5 × 10(-5), 4-6 × 10(-5), and 1-26 × 10(-3), respectively, for the investigated organic substrates. Within experimental uncertainties the uptake of NO(3) was not sensitive to relative humidity levels of 30 and 60%. NO(3) uptake experiments involving substrates of levoglucosan, abietic acid, and the mixture exhibit an initial strong uptake of NO(3) followed by NO(3) gas-phase recovery as a function of NO(3) exposure. In contrast, the uptake of NO(3) by nitroguaiacol continuously proceeds at the same efficiency for investigated NO(3) exposures. The derived oxidative power, i.e. the product of γ and atmospheric oxidant concentration, for applied oxidants is similar or significantly larger in magnitude than for OH, emphasizing the potential importance of these oxidants for particle oxidation. Estimated atmospheric lifetimes for the topmost organic layer with respect to O(3), NO(2), N(2)O(5), and NO(3) oxidation for typical polluted conditions range between 1-112 min, indicating the potential for significant chemical transformation during atmospheric transport. The contact angles determined prior to, and after heterogeneous oxidation by NO(3), representative of 50 ppt for 1 day, do not decrease and thus do not indicate a significant increase in hygroscopicity with potential impacts on water uptake and cloud formation processes.
Doi 10.1039/c1cp22478f
Pmid 22020363
Wosid WOS:000297364300018
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000297364300018
Is Public Yes
Language Text English
Is Qa No