Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 5.414
IF5.414
IF 5-year value: 5.958
IF 5-year
5.958
CiteScore value: 9.7
CiteScore
9.7
SNIP value: 1.517
SNIP1.517
IPP value: 5.61
IPP5.61
SJR value: 2.601
SJR2.601
Scimago H <br class='widget-line-break'>index value: 191
Scimago H
index
191
h5-index value: 89
h5-index89
Volume 9, issue 10
Atmos. Chem. Phys., 9, 3331–3345, 2009
https://doi.org/10.5194/acp-9-3331-2009
© Author(s) 2009. This work is distributed under
the Creative Commons Attribution 3.0 License.
Atmos. Chem. Phys., 9, 3331–3345, 2009
https://doi.org/10.5194/acp-9-3331-2009
© Author(s) 2009. This work is distributed under
the Creative Commons Attribution 3.0 License.

  25 May 2009

25 May 2009

Glyoxal uptake on ammonium sulphate seed aerosol: reaction products and reversibility of uptake under dark and irradiated conditions

M. M. Galloway1, P. S. Chhabra2, A. W. H. Chan2, J. D. Surratt3, R. C. Flagan2,4, J. H. Seinfeld2,4, and F. N. Keutsch1 M. M. Galloway et al.
  • 1Dept. of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
  • 2Dept. of Chemical Engineering, California Institute of Technology, Pasadena, CA, USA
  • 3Dept. of Chemistry, California Institute of Technology, Pasadena, CA, USA
  • 4Dept. of Environmental Science and Engineering, California Institute of Technology, Pasadena, CA, USA

Abstract. Chamber studies of glyoxal uptake onto ammonium sulphate aerosol were performed under dark and irradiated conditions to gain further insight into processes controlling glyoxal uptake onto ambient aerosol. Organic fragments from glyoxal dimers and trimers were observed within the aerosol under dark and irradiated conditions. Glyoxal monomers and oligomers were the dominant organic compounds formed under the conditions of this study; glyoxal oligomer formation and overall organic growth were found to be reversible under dark conditions. Analysis of high-resolution time-of-flight aerosol mass spectra provides evidence for irreversible formation of carbon-nitrogen (C-N) compounds in the aerosol. We have identified 1H-imidazole-2-carboxaldehyde as one C-N product. To the authors' knowledge, this is the first time C-N compounds resulting from condensed phase reactions with ammonium sulphate seed have been detected in aerosol. Organosulphates were not detected under dark conditions. However, active photochemistry was found to occur within aerosol during irradiated experiments. Carboxylic acids and organic esters were identified within the aerosol. An organosulphate, which had been previously assigned as glyoxal sulphate in ambient samples and chamber studies of isoprene oxidation, was observed only in the irradiated experiments. Comparison with a laboratory synthesized standard and chemical considerations strongly suggest that this organosulphate is glycolic acid sulphate, an isomer of the previously proposed glyoxal sulphate. Our study shows that reversibility of glyoxal uptake should be taken into account in SOA models and also demonstrates the need for further investigation of C-N compound formation and photochemical processes, in particular organosulphate formation.

Publications Copernicus
Download
Citation
Altmetrics
Final-revised paper
Preprint