title: Oscillatory behaviour of catalytic properties, structure and temperature during the catalytic partial oxidation of methane on Pd/Al(2)O(3).
abstract: Pd/Al(2)O(3) catalysts showed an oscillatory behaviour during the catalytic partial oxidation (CPO) of methane, which was investigated simultaneously by IR-thermography, X-ray absorption spectroscopy, and online mass-spectrometry to correlate the temperature, state of the catalyst and catalytic performance. The following stages were observed: (i) build-up of a temperature maximum in the first half of the catalyst bed, (ii) reduction of palladium in the end zone of the catalyst bed with a front moving toward the entrance zone, (iii) strong hot spot formation accompanied by reduction of palladium due to self-reduction leading to extinction of the process. The latter was the key driver for the oscillations and thus gave additional insight into the mechanism of partial methane oxidation.
authors.affiliation: Department of Chemistry and Applied Biosciences, ETH Zürich, Hönggerberg-HCI, CH-8093 Zürich, Switzerland. b.kimmerle@chem.ethz.ch
authors.forename: Bertram
authors.initials: B
authors.lastname: Kimmerle
authors.forename: Alfons
authors.initials: A
authors.lastname: Baiker
authors.forename: Jan-Dierk
authors.initials: JD
authors.lastname: Grunwaldt
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D002384:Catalysis; D008697:Methane / Q000737:chemistry*; D015394:Molecular Structure; D009991:Oscillometry; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D013696:Temperature
chemical_list: D010165:Palladium; D000537:Aluminum Oxide; D008697:Methane