Interaction of Propene with Pure and Hydrogen-Precovered Nickel Films. Studied by Means of Isothermal Reaction Mass Spectrometry and Thermal Desorption Spectroscopy

Kleyna, R.; Fickert, Stefan; Borgmann, D.; Wedler, G.

doi:10.1021/la971372x

Cited by 2 publications

(1 citation statement)

References 30 publications

(53 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The suggestion that propene undergoes autohydrogenation over cobalt catalysts is consistent with the literature data. Indeed, propene autohydrogenation has been reported for Pt and Ni catalysts [15,42]. This reaction network seems to be very similar to that found for ethene and propene adsorption on single crystals [10,14,15,43,44].…”

Section: Mechanistic Aspects Of C3 Hydrocarbon Chemisorptionsupporting

confidence: 74%

Chemisorption of C3 hydrocarbons on cobalt silica supported Fischer?Tropsch catalysts

Lermontov¹,

Girardon²,

Griboval-Constant³

et al. 2005

Catal Lett

View full text Add to dashboard Cite

Chemisorption of propene and propane was studied in a pulse reactor over a series of cobalt silica-supported Fischer-Tropsch catalysts. It was shown that interaction of propene with cobalt metal particles resulted in its rapid autohydrogenation. The reaction consists in a part of the propene being dehydrogenated to surface carbon and CH x chemisorbed species; hydrogen atoms released in the course of propene dehydrogenation are then involved in hydrogenation of remaining propene molecules to propane at 323-423 K or in propene hydrogenolysis to methane and ethane at temperatures higher than 423 K. The catalyst characterization suggests that propene chemisorption over cobalt catalysts is primarily a function of the density of cobalt surface metal sites. A correlation between propene chemisorption and Fischer-Tropsch reaction rate was observed over a series of cobalt silica-supported catalysts. No propane chemisorption was observed at 323-373 K over cobalt silica-supported catalysts. Propane autohydrogenolysis was found to proceed at higher temperatures, with methane being the major product of this reaction over cobalt catalysts. Hydrogen for propane autohydrogenolysis is probably provided by adsorbed CH x species formed via propane dehydrogenation. Propene and propane chemisorption is dramatically reduced upon the catalyst exposure to synthesis gas (H 2 /CO = 2) at 323-473 K. Our results suggest that cobalt metal particles are probably completely covered by carbon monoxide molecules under the conditions similar to Fischer-Tropsch synthesis and thus, most of cobalt surface sites are not available for propene and propane chemisorption.

show abstract