 |
| Titel |
Efficient photochemical generation of peroxycarboxylic nitric anhydrides with ultraviolet light-emitting diodes |
| VerfasserIn |
N. D. Rider, Y. M. Taha, C. A. Odame-Ankrah, J. A. Huo, T. W. Tokarek, E. Cairns, S. G. Moussa, J. Liggio, H. D. Osthoff |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 8, no. 7 ; Nr. 8, no. 7 (2015-07-08), S.2737-2748 |
| Datensatznummer |
250116476
|
| Publikation (Nr.) |
 copernicus.org/amt-8-2737-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| Photochemical sources of peroxycarboxylic nitric anhydrides (PANs) are
utilized in many atmospheric measurement techniques for calibration or to
deliver an internal standard. Conventionally, such sources rely on
phosphor-coated low-pressure mercury (Hg) lamps to generate the UV light
necessary to photo-dissociate a dialkyl ketone (usually acetone) in the
presence of a calibrated amount of nitric oxide (NO) and oxygen (O2).
In this manuscript, a photochemical PAN source in which the Hg lamp has been
replaced by arrays of ultraviolet light-emitting diodes (UV-LEDs) is
described. The output of the UV-LED source was analyzed by gas
chromatography (PAN-GC) and thermal dissociation cavity ring-down
spectroscopy (TD-CRDS). Using acetone, diethyl ketone (DIEK), diisopropyl
ketone (DIPK), or di-n-propyl ketone (DNPK), respectively, the source
produces peroxyacetic (PAN), peroxypropionic (PPN), peroxyisobutanoic
(PiBN), or peroxy-n-butanoic nitric anhydride (PnBN) from NO in high yield
(> 90 %). Box model simulations with a subset of the Master
Chemical Mechanism (MCM) were carried out to rationalize product yields and
to identify side products. The present work demonstrates that UV-LED arrays
are a viable alternative to current Hg lamp setups. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|