Hydrogenation of olefin adsorbed on Pt/SiO/sub 2/

Journal Article · Sat Nov 01 04:00:00 EST 1986 · J. Catal.; (United States)

OSTI ID:5536354

Kawai, T; Burwell, Jr, R L

Cyclopentene and cyclooctene have been hydrogenated in a batch reactor on supported platinum catalysts at temperatures such that over 99.99% of the olefin was in the adsorbed state and primarily on the support. Reaction temperatures were -75/sup 0/C for cyclopentene and -22/sup 0/C for cyclooctene and P(H/sub 2/) was usually 100 Torr. At coverages of one molecule of cyclopentene per nm/sub 2/ on Pt/(wide pore silica gel), the rate was zero order in olefin up to a conversion of about 70% following which the rate declined. The rate was about one-half order in hydrogen. Pt/alumina and Pt/silica gel gave similar results. Transport of olefin from the surface of the support to crystallites of platinum occurred primarily by surface migration rather than through the vapor phase. Significant contribution to hydrogenation by hydrogen spillover from platinum to silica can be excluded. Small particles of platinum on silica gel gave somewhat larger values of turnover frequency, N/sub t/, than did larger particles, at least after the pretreatment O/sub 2/, 300/sup 0/C; He, 450/sup 0/C; cool in He. N/sub t/ for cyclopentene was roughly equal to that for propylene in conventional vapor phase hydrogenation extrapolated to -75/sup 0/C.

• Research Organization: Northwestern Univ., Evanston, IL
• OSTI ID: 5536354
• Journal Information: J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 102:1; ISSN JCTLA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ADSORPTION
ALKENES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CATALYSIS
CATALYST SUPPORTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
CYCLOALKENES
ELEMENTS
HYDROCARBONS
HYDROGENATION
KINETICS
METALS
MINERALS
ORGANIC COMPOUNDS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PLATINUM
PLATINUM METALS
REACTION KINETICS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SORPTION
TRANSITION ELEMENTS