A shock tube, laser-schlieren study of propene pyrolysis at high

J. H. Kiefer, M. Z. Al-Alami, and K. A. Budach. J. Phys. Chem. , 1982, 86 (5), pp 808–813. DOI: 10.1021/j100394a043. Publication Date: March 1982...
0 downloads 0 Views 711KB Size
J. Phys. Chem. 1982, 86,808-813

808

A Shock Tube, Laser-Schlieren Study of Propene Pyrolysis at High Temperatures J. H. Klefer,' M. 2. Al-Alaml, and K. A. Budach Department of Energy Engineering, University of Illinois at Chicago Circle, Chicago, Illinois 60680 (Received Ju/y 3 7, 198 1; I n Final Form: September 8, 798 1)

-

Laser-schlieren, shock tube methods have been used to determine the rate of initiation in propene pyrolysis. Given that the dominant initiation reaction is M + C3Hs CH3+ C2H3 + M, the rate constant over 1650-2300 K and 1X lo4 C (M) C 2.2 X lo4 mol/cm3is 5.4 X 1075T15.7 exp[-120000/(RT)] cm3/(mols) (R in cal/(mol K)). There is no clear difference between C3H6and Kr as M. This rate was obtained by a computer simulation assisted extrapolation to the presumed instant of shock heating ( t = 0) and the derivation of an initial rate by using calculated frozen reaction conditions. This rate is in reasonable agreement with previous single-pulse shock tube measurements,and suggests that the reaction is in the falloff region in all the shock-tubestudies. A possible contribution by C3H6 C3H5+ H cannot be excluded.

-

The pyrolysis of propene has been extensively investigated at low temperatures (