Vinylic initiation of the Fischer-Tropsch reaction over ruthenium on silica catalysts
- Univ. of Sheffield (United Kingdom); and others
Vinylic probes were added to a ruthenium-catalysed Fischer-Tropsch reaction in order to study the mechanism of hydrocarbon formation from CO/H{sub 2}. {sup 13}C{sub 2} units derived from {sup 13}CH{sub 2}={sup 13}CHBr or {sup 13}CH{sub 2}={sup 13}CH{sub 2} are readily incorporated into the alkene and alkane products formed from {sup 12}CO and H{sub 2} over a Ru/SiO{sub 2} catalyst (1 atm, 180{degrees}C). The levels of {sup 13}C{sub 2} incorporation suggest that the probes are sources of {sup 13}C{sub 2}-labelled initiating units, proposed to be surface vinyls (-CH=CH{sub 2}). Further evidence for vinyl initiation is given by the increase in hydrocarbon formation rate during vinylic probe addition. This rate increase is not observed when ethyl bromide is added as a probe and shows the significance of the unsaturated initiating unit. {sup 13}C{sub 4} incorporation in the C{sub 4} hydrocarbon products (especially cis-2-butene) is attributed to a facile vinyl dimerisation reaction, as previously observed on rhodium catalysts and in discrete organometallic complexes. Hydrogenolysis of the {sup 13}C{sub 2}-probes was an appreciable side reaction over Ru/SiO{sub 2} and resulted in some incorporation of {sup 13}C{sub 1} units. 31 refs., 6 figs., 2 tabs.
- OSTI ID:
- 563508
- Journal Information:
- Journal of Catalysis, Vol. 167, Issue 1; Other Information: PBD: 1 Apr 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
An isotopic tracer study of the deactivation of Ru/TiO sub 2 catalysts during Fischer-Tropsch synthesis
Influence of support on K promotion of Ru for the Fischer-Tropsch synthesis