Liquid-phase hydrogenation of cyclohexene over Pt foil catalysts

Journal Article · Mon Jan 01 04:00:00 EST 1996 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1996.0018· OSTI ID:223980

Gardin, D E; Su, X; Cremer, P S; Somorjai, G A ^[1]

---

1. Lawrence Berkeley Lab., CA (United States)

A liquid-phase reaction cell, coupled to an ultrahigh-vacuum surface analysis chamber, was built to study liquid-phase hydrogenation reactions on small area model catalyst surfaces. The hydrogenation of cyclohexene to cyclohexane was studied at about 1.5 atm total pressure of H{sub 2} and as a function of temperature in the 313-333 K range in liquid cyclohexene. The hydrogenation rate of cyclohexene on a clean Pt surface increased with the increasing circulation velocity of the liquid, indicating that the reaction rate was controlled by hydrogen diffusion to the surface. When the surface reaction rate was reduced by the deposition of hydrocarbon fragments on the platinum surface, the rate of cyclohexene hydrogenation became independent of hydrogen diffusion and became controlled by the kinetics of the surface reaction. The estimated activation energy of the reaction is 6 kcal/mol for cyclohexene hydrogenation on a platinum foil that was partly covered with carbonaceous deposits. 10 refs., 5 figs., 1 tab.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 223980
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 1 Vol. 158; ISSN 0021-9517; ISSN JCTLA5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
40 CHEMISTRY
ACTIVATION ENERGY
CATALYSTS
CATALYTIC EFFECTS
CHEMICAL REACTION KINETICS
CYCLOALKENES
HYDROGENATION
PLATINUM