ISSN:
1572-879X
Keywords:
Propylene conversion
;
metathesis
;
hydrogenolysis
;
methylcyclopropane formation
;
cyclization
;
Mo(100) catalyst
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Analysis of the products formed in the Mo(100) single crystal-catalyzed decomposition of propylene using an isolatable high-pressure reactor shows that this surface simultaneously catalyzes metathesis, hydrogenolysis and also methylcyclopropane formation. The activation energy for olefin metathesis on Mo(100) is measured to be 65±1 kcal/mole, and the reaction is first order in propylene pressure. These results are consistent with the reaction proceeding via a carbene mechanism on Mo(100) since hydrogenolysis indicates that carbon-carbon bonds can cleave selectively, and methylcyclopropane formation suggests that a metallacycle has formed. The observed first-order reaction kinetics are also in accord with this view. Pre-dosing the Mo(100) surface with a monolayer of oxygen reduces the catalytic activity by a factor of ∼ 17. This implies that the four-fold hollow site is active for propylene metathesis on Mo(100) since atomic oxygen adsorbs at this site.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00764060
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