The formation of hydrogen in ethylene pyrolysis at 900 K

✍ Scribed by Indira S. Jayaweera; Philip D. Pacey

• Publisher: John Wiley and Sons
• Year: 1988
• Tongue: English
• Weight: 489 KB
• Volume: 20
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550200906

✦ Synopsis

Ethylene a t concentrations of 2.7 X to 1.0 x mol L ' has been pyrolyzed at 900 K in a flow system. The products ethane and hydrogen have been analyzed by gas chromatography. The results are consistent with a mechanism in which these products are initially formed as follows:

L11 141

Reaction [11 occurs only 1 to 2% as often as the addition reaction,

CZHS

The latter reaction is close to equilibrium. Taking the rate constant, k4, and the equilibrium constant, K 2 , from the literature and making small adjustments for minor processes, k , is found to be (9 ? 3) x lo7 L mol-'s-'. Here the uncertainty is intended to encompass errors in the present work and in the literature parameters.

A secondary source of hydrogen was also observed. Its dependence on ethylene concentration was consistent with formation from an intermediate with six carbon atoms, such as cyclohexene.