1. An experimental and theoretical high temperature kinetic study of the thermal unimolecular dissociation of fluoroethane.
- Author
-
Binod R. GiriCurrent address: Department of Chemistry, Acadia University, Wolfville, Nova Scotia, Canada., John. H. Kiefer, Hui XuCurrent address: Cummins Inc., Cummins Technical Center, 1900 McKinley Ave, Columbus, IN-47201, USA., Stephen J. Klippenstein, and Robert S. Tranter
- Abstract
The thermal dissociation of fluoroethane has been studied using shock tube (ST)/time-of-flight mass spectrometry (TOF-MS) at 500 and 1200 Torr over the temperature range 1200–1550 K. The ST/TOF-MS experiments confirm that elimination of HF is the only reaction channel and rate coefficients for this reaction were extracted from concentration/time profiles derived from the mass spectra. Results from a novel diaphragmless shock tube coupled to the TOF-MS are also presented and demonstrate the unique ability of this apparatus to generate sufficiently reproducible shock waves that signal averaging can be performed over multiple experiments; something that is not possible with a conventional shock tube. The dissociation is also studied with ab initio transition state theory based master equation simulations. A modest increase in the calculated barrier height (i.e., by 1 kcal mol−1) yields predicted high pressure rate coefficients that are in good agreement with the existing literature data. The present pressure dependent observations are accurately reproduced for a downwards energy transfer for neon at 1200 to 1500 K of ∼270 cm−1, which is somewhat smaller than that found in previous studies on fluorinated ethanes with the same bath gases. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF