ABSTRACT The reactions of chlorine (Cl) atoms with volatile organic compounds (VOCs) emitted into the atmosphere are of special interest to understand the role of Cl in the marine and coastal chemistry. In this review we summarize the most recent results obtained in our laboratories concerning the kinetic and products study of the Cl atoms reactions with a series of heterocyclic compounds. We report here kinetic measurements of the reactions of atomic Cl with furan, 2-methylfuran, 3-methylfuran, 2-ethylfuran, 2,5-dimethylfuran, 2-furanaldehyde, 3-furanaldehyde and 5-methyl-2-furanaldehyde. The reactions were studied at 298K and 1 atm using a relative rate technique with GC-FID/MS detection of the organic compounds and different Cl-atom precursors. To assess the atmospheric relevance of these reactions, products of some of the indicated reactions were determined under atmospheric conditions. For products study two different sampling/detection methods have been used: (1) Solid-Phase Micro Extraction, with subsequent analysis by thermal desorption, and gas chromatography with mass spectrometry or flame ionization detection (SPME/GC-MS/FID), and (2) ‘‘in situ’’ with long path Fourier Transform Infrared Spectroscopy (FTIR). The influence of the structure on the reactivity of these compounds, their reaction mechanisms and the atmospheric implications are also discussed. It is important to mention that we have reported the first kinetics and products measurements of all the considered reactions.
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