Kinetics of cyclohexane dehydrogenation and hydrogenolysis over Rh(0001) and Cu/Ru(0001)

Journal Article · Wed Apr 01 04:00:00 EST 1987 · J. Catal.; (United States)

OSTI ID:5323008

Peden, C H.F.; Goodman, D W

The kinetics of cyclohexane dehydrogenation and hydrogenolysis have been measured on initially clean Ru(0001) and Ru(0001) precovered with submonolayer quantities of Cu. The agreement between the results obtained on the model systems with those previously measured on supported catalysts attests to the appropriateness of the model. Postreaction surface analysis of Ru(0001) revealed the presence of a carbonaceous deposit, the amount of which correlated with the reaction rates. Further, this carbon deposit was observed to increase in amount during the initial stages of reaction (induction period), ceasing to grow at a time coinciding with the onset of steady-state reaction. Hydrogenolysis and dehydrogenation rates were greater and smaller during the induction period, respectively, than at steady state. These results suggest that steady-state reaction is occurring on carbon-modified Ru. Addition of Cu results in an enhanced activity for the dehydrogenation of cyclohexane to benzene, occurring with little or no induction time. The mechanism by which Cu alters the catalytic activity of Ru may involve an electronic modification of either or both of the catalyst metals, and/or a synergism between the activities of the two metal components.

• Research Organization: Sandia National Labs., Albuquerque, NM
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5323008
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 104:2; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ALKANES
AROMATICS
BENZENE
CARBONACEOUS MATERIALS
CATALYTIC EFFECTS
CATALYTIC REFORMING
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
COPPER
CRYSTAL FACES
CYCLOALKANES
CYCLOHEXANE
DEHYDROGENATION
DEPOSITION
ELEMENTS
HYDROCARBONS
KINETICS
MATERIALS
METALS
ORGANIC COMPOUNDS
PLATINUM METALS
PROMOTERS
REACTION KINETICS
REFORMER PROCESSES
RHODIUM
SYNERGISM
TRANSITION ELEMENTS