Influence of particle size and support on the catalytic properties of rhodium for hydrogenolysis of hexanes and methylcyclopentane
The catalytic properties of rhodium for the hydrogenolysis of C/sub 6/ hydrocarbons have been investigated. Rhodium preferentially cleaves bisecondary and primary-secondary carbon-carbon bonds. Primary-tertiary C-C bonds react much more slowly. Methylcyclopentane (MCP) is converted to methyl-2-pentane, methyl-3-pentane, and n-hexane at temperatures lower than 503 K. The selectivity to n-hexane is low (10%) but measurable on well-dispersed Rh/Al/sub 2/O/sub 3/ catalysts and decreases when the dispersion decreases. Rh/SiO/sub 2/ catalysts have a low selectivity for the formation of n-hexane whatever the dispersion. The specific activity for MCP conversion changes as a function of the dispersion of rhodium and of the support: small rhodium particles are more active than large particles when the support is silica, but the reverse is true on alumina. These changes of activity are consistent with the results reported for C/sub 2/H/sub 6/ hydrogenolysis on Rh/SiO/sub 2/ and for C/sub 5/H/sub 10/ conversion on Rh/Al/sub 2/O/sub 3/. The variations of the catalytic properties for hydrogenolysis may be interpreted as due to the modification of the structure of the small rhodium particles observed on silica.
- Research Organization:
- Laboratoire de Chimie Organique Physique et Cinetique Chimique Appliquees, Montpellier, France
- OSTI ID:
- 6715105
- Journal Information:
- J. Catal.; (United States), Journal Name: J. Catal.; (United States) Vol. 87:1; ISSN JCTLA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Reactions of n-hexane and methylcyclopentane over dispersed cobalt-rhodium catalysts: synergism in catalysis by alloys
Methylcyclopentane conversion catalysis over zeolite-Y encaged rhodium: A test for the metal-proton adduct model