Kinetics of acid-catalyzed aldol condensation reactions of aliphatic aldehydes

Title:
Kinetics of acid-catalyzed aldol condensation reactions of aliphatic aldehydes
Authors:
Casale, Mia T.; Richman, Aviva R.; Elrod, Matthew J.; Garland, Rebecca M.; Beaver, Melinda R.; Tolbert, Margaret A.
Abstract:
Field observations of atmospheric aerosols have established that organic compounds compose a large fraction of the atmospheric aerosol mass. However, the physical/chemical pathway by which organic compounds are incorporated into atmospheric aerosols remains unclear. The potential role of acid-catalyzed reactions of organic compounds on acidic aerosols has been explored as a possible chemical pathway for the incorporation of organic material into aerosols. In the present study, ultravioletâ visible (UVâ vis) spectroscopy was used to monitor the kinetics of formation of the products of the acid-catalyzed aldol condensation reaction of a range of aliphatic aldehydes (C2â C8). The experiments were carried out at various sulfuric acid concentrations and a range of temperatures in order to estimate the rate constants of such reactions on sulfuric acid aerosols under tropospheric conditions. The rate constants were generally found to decrease as the chain length of the aliphatic aldehyde increased (except for acetaldehyde, which had an unusually small rate constant), increase as a function of sulfuric acid concentration as predicted by excess acidity theory, and showed normal Arrhenius behavior as a function of temperature. While the kinetic data are generally consistent with previous laboratory reports of aldehyde reactivity in various sulfuric acid media, the aldol condensation reactions involving aliphatic aldehydes do not appear fast enough to be responsible for significant transfer of organic material into atmospheric aerosols.
Citation:
Casale, M.T., A.R. Richman, M.J. Elrod, R.M. Garland, M.R. Beaver, and M.A. Tolbert. 2007. "Kinetics of Acid-Catalyzed Aldol Condensation Reactions of Aliphatic Aldehydes." Atmospheric Environment 41(29): 6212-6224.
Publisher:
Elsevier
DATE ISSUED:
2007-09
Department:
Chemistry
Type:
article
PUBLISHED VERSION:
10.1016/j.atmosenv.2007.04.002
PERMANENT LINK:
http://hdl.handle.net/11282/309718

Full metadata record

DC FieldValue Language
dc.contributor.authorCasale, Mia T.en_US
dc.contributor.authorRichman, Aviva R.en_US
dc.contributor.authorElrod, Matthew J.en_US
dc.contributor.authorGarland, Rebecca M.en_US
dc.contributor.authorBeaver, Melinda R.en_US
dc.contributor.authorTolbert, Margaret A.en_US
dc.date.accessioned2013-12-23T16:16:15Zen
dc.date.available2013-12-23T16:16:15Zen
dc.date.issued2007-09en
dc.identifier.citationCasale, M.T., A.R. Richman, M.J. Elrod, R.M. Garland, M.R. Beaver, and M.A. Tolbert. 2007. "Kinetics of Acid-Catalyzed Aldol Condensation Reactions of Aliphatic Aldehydes." Atmospheric Environment 41(29): 6212-6224.en_US
dc.identifier.issn1352-2310en_US
dc.identifier.urihttp://hdl.handle.net/11282/309718en
dc.description.abstractField observations of atmospheric aerosols have established that organic compounds compose a large fraction of the atmospheric aerosol mass. However, the physical/chemical pathway by which organic compounds are incorporated into atmospheric aerosols remains unclear. The potential role of acid-catalyzed reactions of organic compounds on acidic aerosols has been explored as a possible chemical pathway for the incorporation of organic material into aerosols. In the present study, ultravioletâ visible (UVâ vis) spectroscopy was used to monitor the kinetics of formation of the products of the acid-catalyzed aldol condensation reaction of a range of aliphatic aldehydes (C2â C8). The experiments were carried out at various sulfuric acid concentrations and a range of temperatures in order to estimate the rate constants of such reactions on sulfuric acid aerosols under tropospheric conditions. The rate constants were generally found to decrease as the chain length of the aliphatic aldehyde increased (except for acetaldehyde, which had an unusually small rate constant), increase as a function of sulfuric acid concentration as predicted by excess acidity theory, and showed normal Arrhenius behavior as a function of temperature. While the kinetic data are generally consistent with previous laboratory reports of aldehyde reactivity in various sulfuric acid media, the aldol condensation reactions involving aliphatic aldehydes do not appear fast enough to be responsible for significant transfer of organic material into atmospheric aerosols.en_US
dc.language.isoen_USen_US
dc.publisherElsevieren_US
dc.identifier.doi10.1016/j.atmosenv.2007.04.002en
dc.subject.departmentChemistryen_US
dc.titleKinetics of acid-catalyzed aldol condensation reactions of aliphatic aldehydesen_US
dc.typearticleen_US
dc.identifier.journalAtmospheric Environmenten_US
dc.subject.keywordTroposphereen_US
dc.subject.keywordOrganic aerosolsen_US
dc.subject.keywordAcid-catalyzed reactionsen_US
dc.subject.keywordKineticsen_US
dc.identifier.volume41en_US
dc.identifier.issue29en_US
dc.identifier.startpage6212en_US
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