title: Improved Performance of Ru/γ-Al2O3 Catalysts in the Selective Methanation of CO in CO2-Rich Reformate Gases upon Transient Exposure to Water-Containing Reaction Gas.
abstract: To better understand the role of water in the selective methanation of CO in CO2-rich reformate gases on Ru/Al2O3 catalysts, the influence of exposing these catalysts to H2O-rich reformate gases on their reaction characteristics in transient experiments was investigated by employing kinetic and in situ spectroscopic measurements as well as ex situ catalyst characterization. Transient exposure of the ruthenium catalyst to wet reaction gas (5 or 15% H2O) results in significantly enhanced activity and selectivity for CO methanation in subsequent reactions in dry reformate compared with activation and reaction in dry reformate directly. Operando X-ray absorption spectroscopy results reveal that this is in accordance with a significant decrease in ruthenium particle size, which is stable during subsequent reaction in dry reformate. The implications of these data and additional results from in situ IR spectroscopy on the role and influence of H2O on the reaction, also in technical applications, are discussed.
authors.affiliation: Institute of Surface Chemistry and Catalysis, Ulm University, 89069, Ulm, Germany.|Department of Chemistry, Faculty of Science, Cairo University, Giza, 12613, Egypt.
authors.forename: Ali M
authors.initials: AM
authors.lastname: Abdel-Mageed
authors.affiliation: Institute of Surface Chemistry and Catalysis, Ulm University, 89069, Ulm, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Widmann
authors.affiliation: Clariant Produkte (Deutschland) GmbH/Clariant SE, Lenbachplatz 6, 80330, Munich, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Eckle
authors.affiliation: Institute of Surface Chemistry and Catalysis, Ulm University, 89069, Ulm, Germany. juergen.behm@uni-ulm.de.
authors.forename: R Jürgen
authors.initials: RJ
authors.lastname: Behm
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry*; D002384:Catalysis; D007700:Kinetics; D053768:Metal Nanoparticles / Q000737:chemistry; D008697:Methane / Q000737:chemistry*; D010084:Oxidation-Reduction; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D002245:Carbon Dioxide; D002248:Carbon Monoxide; D012428:Ruthenium; D000537:Aluminum Oxide; D008697:Methane
keywords: methanation; nanoparticles; ruthenium; supported catalysts; surface analysis