Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Diode laser study of the Cl + C[sub 2]H[sub 5] reaction

Journal Article · · Journal of Physical Chemistry; (United States)
DOI:https://doi.org/10.1021/j100132a028· OSTI ID:6019430
; ;  [1]
  1. Ford Motor Company, Dearborn, MI (United States)

Real time IR absorption measurements of the formation of C[sub 2]H[sub 4] and HCl following the Cl initiated chain reaction between chlorine and ethane are presented. The ethylene molecules, formed by the reaction between chlorine atoms and ethyl radicals, arc born highly vibrationally excited and are only slowly relaxed in a N[sub 2] bath gas. The addition of C[sub 2]F[sub 6] provides efficient vibrational relaxation and reveals a very fast rise in the ethylene concentration. The measured Cl + C[sub 2]H[sub 5] rare constant is k[sub 3](295 K) = (2.9 [+-] 0.6) X 10[sup [minus]10] cm[sup 3] s[sup [minus]1] and resolves a discrepancy of a factor of 20 in previous reports of this rate constant. Measurements of the HCl concentration reveal a relatively short chain length under conditions for which the steady-state Cl and C[sub 2]H[sub 5] concentrations are comparable. Fits of the [HCl] time dependence yield a value of k[sub 3] = (3.4 [+-] 0.6) X 10[sup [minus]10] cm[sup 3] s[sup [minus]1] for the Cl + C[sub 2]H[sub 5] rate constant, in agreement with the value derived from the formation of C[sub 2]H[sub 4]. We have also measured the rate constant for the addition of chlorine atoms to ethylene and find that k[sub 6] = (1.4 [+-] 0.2) X 10[sup [minus]11] and (3.5 [+-] 0.7) X 10[sup [minus]11] cm[sup 3] s[sup [minus]1] respectively at 30 and 120 Torr total pressure and 295 K, in good agreement with literature values. 31 refs., 7 figs., 6 tabs.

OSTI ID:
6019430
Journal Information:
Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 97:30; ISSN JPCHAX; ISSN 0022-3654
Country of Publication:
United States
Language:
English