References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-7-1565-2007

Daytime tropospheric loss of hexanal and trans-2-hexenal: OH kinetics and UV photolysis

Jiménez

¹ Lanza

¹ Martínez

¹ Albaladejo

Departamento de Química Física, Facultad de Ciencias Químicas, Universidad de Castilla-La Mancha, Avda. Camilo José Cela, s/n. 13071 Ciudad Real, Spain

22 03 2007

7 6 1565 1574

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.atmos-chem-phys.net/7/1565/2007/acp-7-1565-2007.html

The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/1565/2007/acp-7-1565-2007.pdf

The ultraviolet (λ=250–370 nm) photolysis and the OH-initiated oxidation of hexanal and trans-2-hexenal, which are relevant atmospheric processes, have been investigated at room temperature and as a function of temperature (T=263–353 K), respectively. This kinetic study as a function of temperature is reported here for the first time. Absolute absorption cross sections (σλ) were obtained using a recently built system operating in the UV region. The obtained σλ allowed the estimation of the photolysis rates (J) across the troposphere. Kinetic measurements of the gas-phase reaction of hydroxyl radicals (OH) with hexanal and trans-2-hexenal were performed by using the laser pulsed photolysis/laser-induced fluorescence technique. Rate coefficients kOH for both aldehydes were determined at temperatures between 263 and 353 K at 50 Torr in helium or argon bath gases. The temperature dependence of kOH for both aldehydes was found to be slightly negative. The tropospheric lifetime of hexanal and trans-2-hexenal due to the chemical removal by OH radicals has been estimated across the troposphere. The loss rate due to the OH chemical removal was compared with the estimated photolysis rates. Our results show that OH-reaction is the main loss process for these aldehydes in the troposphere, although photolysis is not negligible for hexanal.

References 1

Albaladejo, J., Ballesteros, B., Jiménez, E., Martín, P., and Martínez, E.: A PLP-LIF kinetic study of the atmospheric reactivity of a series of C4-C$_7$ saturated and unsaturated aliphatic aldehydes with OH, Atmos. Environ., 36, 3231–3239, 2002.

Atkinson, R. and Arey, J.: Atmospheric degradation of volatile organic compounds, Chem. Rev., 103, 4605–4638, 2003.

Atkinson, R., Arey, J., Aschmann, S. M., Corchnoy, S. B., and Shu, Y.: Rate constants for the gas-phase reactions of \textitcis-3-hexen-1-ol, \textitcis-3-hexenylacetate, \textittrans-2-hexenal, and linalool with OH and NO3 radicals and O3 at 296$\pm $2 K, and OH radical formation yields from the O3 reactions, Int. J. Chem. Kinet., 27, 941–955, 1995.

Cabañas, B., Martín, P., Salgado, S., Ballesteros, B., and Martínez, E.: An experimental study on the temperature dependence for the gas-phase reactions of NO3 radical with a series of aliphatic aldehydes, J. Atmos. Chem., 40, 23–39, 2001.

D'Anna, B., Andresen, $\Phi$., Gefen, Z., and Nielsen, C. J.: Kinetic study of OH and NO3 radical reactions with 14 aliphatic aldehydes, Phys. Chem. Chem. Phys., 3, 3057–3063, 2001.

Finlayson-Pitts, B. J. and Pitts Jr., J. N.: Chemistry of the Upper and Lower Atmosphere, Academic Press, San Diego, 2000.

Grosjean, D. and Williams, E. L.: Environmental persistence of organic compounds estimated from structure reactivity and linear free-energy relationships unsaturated aliphatics, Atmos. Environ., 26, 1395–1405, 1992.

Grosjean, D., Grosjean, E., and Gertler, A. W.: On-road emissions of carbonyls from light-duty and heavy-duty vehicles, Environ. Sci. Technol., 35, 45–53, 2001.

Grosjean, E., Grosjean, D., and Seinfeld, J. H.: Gas-phase reaction of ozone with \textittrans-2-hexenal, \textittrans-2-hexenyl acetate, ethylvinyl ketone, and 6-methyl-5-hepten-2-one, Int. J. Chem. Kinet., 28, 373–382, 1996.

Jiménez, E., Lanza, B., Garzón, A., Ballesteros, B., and Albaladejo, J.: Atmospheric degradation of 2-butanol, 2-methyl-2-butanol, and 2,3-dimethyl-2-butanol: OH kinetics and UV absorption cross sections, J. Phys. Chem. A, 109, 10 903–10 909, 2005a.

Jiménez, E., Ballesteros, B., Martínez, E., and Albaladejo, J.: Tropospheric reaction of OH with selected linear ketones: Kinetic studies between 228 and 405 K, Environ. Sci. Technol., 39, 814–820, 2005b.

Jiménez, E., Lanza, B., Ballesteros, B., and Albaladejo, J.: Atmospheric fate of hexanal and trans-2-hexenal: OH kinetic reaction and UV photolysis. 19th International Symopsium on Gas Kinetics. Orléans, France, 2006.

Keller-Rudek, H. and Moortgat, G. K.: MPI-Mainz-UV-VIS Spectral Atlas of Gaseous Molecules, http://www.atmosphere.mpg.de/enid/, 2006.

Kirstine, W., Galbally, I., Ye, Y. R., and Hooper, M.: Emissions of volatile organic compounds (primarily oxygenated species) from pasture, J. Geophys. Res. Atmos., 103, 10 605–10 619, 1998.

Krol, M., van Leeuwen, P. J., and Lelieveld, J.: Global OH trend inferred from methylchloroform measurements, J. Geophys. Res. Atmos., 103, 10 697–10 711, 1998.

Kwok, E. S. C. and Atkinson, R.: Estimation of hydroxyl radical reaction rate constants for gas-phase organic compounds using structure-reactivity relationship: an update, Atmos. Environ., 29, 1685–1695, 1995.

Logan, J. A.: Tropospheric ozone-seasonal behavior, trends, and anthropogenic influence, J. Geophys. Res. Atmos., 90, 10 463–10 482, 1985.

Madronich, S. and Flocke, S.: The role of solar radiation in atmospheric chemistry in Handbook of environmental chemistry, edited by: Boule, P., 1999.

Magneron, I., Thevenet, R., Mellouki, A., Le Bras, G., Moortgat, G. K., and Wirtz, K.: A study of the photolysis and OH-initiated oxidation of acrolein and \textittrans-crotonaldehyde, J. Phys. Chem. A, 106, 2526–2537, 2002.

Moortgat, G. K.: Important photochemical processes in the atmosphere, Pure Appl. Chem., 73, 487–490, 2001.

O'Connor, M. P., Wenger, J. C., Mellouki, A.; Wirtz, K., and Muñoz, A.: The atmospheric photolysis of $E$-2-hexenal, $Z$-3-hexenal and $E$,$E$-2,4-hexadienal, Phys. Chem. Chem. Phys., 8, 5236–5246, 2006.

Owen, S., Boissard, C., Street, R. A., Duckham, S. C., Csiky, O., and Hewitt, C. N.: Screening of 18 Mediterranean plant species for volatile organic compound emissions, Atmos. Environ., 31, 101–117, 1997.

Papagni, C., Arey, J., and Atkinson, R.: Rate constants for the gas-phase reactions of a series of C3-C$_6$ aldehydes with OH and NO3 radicals, Int. J. Chem. Kinet., 32, 79–84, 2000.

Plagens, H.: Untersuchungen zum atmosphärenchemischen Abbau langkettiger Aldehyde, Thesis, University of Wuppertal (Germany), 2001.

Rodríguez, D., Rodríguez, A., Notario, A., Aranda, A., Diaz-de-Mera, Y., and Martinez, E.: Kinetic study of the gas-phase reaction of atomic chlorine with a series of aldehydes, Atmos. Chem. Phys., 5, 3433–3440, 2005.

Sander, S. P., Finlayson-Pitts, B. J., Friedl, R. R., Golden, D. M., Huie, R. E., Kolb, C. E., Kurylo, M. J., Molina, M. J., Moortgat, G. K., Orkin, V. L., and Ravishankara, A. R.: Chemical kinetics and photochemical data for use in atmospheric studies. Evaluation Number 14, JPL Pub. 02-05, Jet Propulsion Laboratory, Pasadena, 2002.

Smith, I. W. M. and Ravishankara, A. R.: Role of hydrogen-bonded intermediates in the bimolecular reactions of the hydroxyl radical, J. Phys. Chem. A, 106, 4798–4807, 2002.

Tadic, J., Juranic, I., and Moortgat G. K.: Photooxidation of $n$-hexanal in air, Molecules, 6, 287–299, 2001.

Tang, Y. X. and Zhu, L.: Wavelength-dependent photolysis of $n$-hexanal and n-heptanal in the 280–330-nm region, J. Phys. Chem. A, 108, 8307–8316, 2004.

Wildt, J., Kobel, K., Schuh-Thomas, G., and Heiden, A. C.: Emissions of oxygenated volatile organic compounds from plants part II: emissions of eaturated aldehydes, J. Atmos. Chem., 45, 173–196, 2003.