TAP study on carbon monoxide oxidation over supported gold catalysts Au/Ti(OH)*4 and Au/Fe(OH)*3: Moisture effect

Hdl Handle:
http://hdl.handle.net/10149/98954
Title:
TAP study on carbon monoxide oxidation over supported gold catalysts Au/Ti(OH)*4 and Au/Fe(OH)*3: Moisture effect
Authors:
Olea, M. (Maria); Tada, M. (Mizuki); Iwasawa, Y. (Yasuhiro)
Affiliation:
The University of Tokyo. Graduate School of Science. Department of Chemistry.
Citation:
Olea, M., Tada, M. and Iwasawa, Y. (2007) 'TAP study on carbon monoxide oxidation over supported gold catalysts Au/Ti(OH)*4 and Au/Fe(OH)*3: Moisture effect', Journal of Catalysis, 248 (1), pp.60-67.
Publisher:
Elsevier
Journal:
Journal of Catalysis
Issue Date:
15-May-2007
URI:
http://hdl.handle.net/10149/98954
DOI:
10.1016/j.jcat.2007.03.004
Abstract:
The effect of moisture on the behavior of the active supported gold catalysts developed by us, Au/Ti(OH)*4 (I) and Au/Fe(OH)*3 (II), during CO activation and CO oxidation in the temperature range 298-473 K was investigated by the temporal analysis of products (TAP) technique. The oxidation reaction over the Au/Ti(OH)*4 catalyst was totally suppressed by the presence of water, independent of the water content of 200 and 1000 ppm, the carbon monoxide-to-oxygen ratio, and the temperature. In contrast, the presence of water vapors showed no effect on CO oxidation over the Au/Fe(OH)*3 catalyst. For both catalysts, the carbon monoxide adsorption feature was unalterable by the presence of water, namely CO molecules reversibly adsorbed on the catalyst surface, but the amount of CO adsorbed decreased by increasing water content. When a reaction mixture at a 1:1 ratio of CO to O2 was pulsed on the catalyst in the absence of water, the CO response curve showed two peaks, whereas in the presence of water, the TAP response curve showed only one peak. At a 1:3 CO-to-O2 ratio, the CO response curve showed only one peak, which shifted to a shorter time and narrowed in the absence of water. The shift was more pronounced on catalyst (II). The TAP experiments provided indirect evidence that CO and water adsorbed together (CO weakly and water strongly) and water blocked [irreversibly for Au/Ti(OH)*4 and reversibly for Au/Fe(OH)*3], the adsorption sites for oxygen.
Type:
Article
Language:
en
Keywords:
carbon monoxide oxidation; moisture effect; reaction mechanism; supported gold catalyst; TAP study
ISSN:
0021-9517; 1090-2694
Rights:
Author can archive post-print (ie final draft post-refereeing). For full details see http://www.sherpa.ac.uk/romeo/ [Accessed 17/05/2010]
Citation Count:
2 [Scopus, 17/05/2010]

Full metadata record

DC FieldValue Language
dc.contributor.authorOlea, M. (Maria)en
dc.contributor.authorTada, M. (Mizuki)en
dc.contributor.authorIwasawa, Y. (Yasuhiro)en
dc.date.accessioned2010-05-17T08:17:34Z-
dc.date.available2010-05-17T08:17:34Z-
dc.date.issued2007-05-15-
dc.identifier.citationJournal of Catalysis; 248(1):60-67en
dc.identifier.issn0021-9517-
dc.identifier.issn1090-2694-
dc.identifier.doi10.1016/j.jcat.2007.03.004-
dc.identifier.urihttp://hdl.handle.net/10149/98954-
dc.description.abstractThe effect of moisture on the behavior of the active supported gold catalysts developed by us, Au/Ti(OH)*4 (I) and Au/Fe(OH)*3 (II), during CO activation and CO oxidation in the temperature range 298-473 K was investigated by the temporal analysis of products (TAP) technique. The oxidation reaction over the Au/Ti(OH)*4 catalyst was totally suppressed by the presence of water, independent of the water content of 200 and 1000 ppm, the carbon monoxide-to-oxygen ratio, and the temperature. In contrast, the presence of water vapors showed no effect on CO oxidation over the Au/Fe(OH)*3 catalyst. For both catalysts, the carbon monoxide adsorption feature was unalterable by the presence of water, namely CO molecules reversibly adsorbed on the catalyst surface, but the amount of CO adsorbed decreased by increasing water content. When a reaction mixture at a 1:1 ratio of CO to O2 was pulsed on the catalyst in the absence of water, the CO response curve showed two peaks, whereas in the presence of water, the TAP response curve showed only one peak. At a 1:3 CO-to-O2 ratio, the CO response curve showed only one peak, which shifted to a shorter time and narrowed in the absence of water. The shift was more pronounced on catalyst (II). The TAP experiments provided indirect evidence that CO and water adsorbed together (CO weakly and water strongly) and water blocked [irreversibly for Au/Ti(OH)*4 and reversibly for Au/Fe(OH)*3], the adsorption sites for oxygen.en
dc.language.isoenen
dc.publisherElsevieren
dc.rightsAuthor can archive post-print (ie final draft post-refereeing). For full details see http://www.sherpa.ac.uk/romeo/ [Accessed 17/05/2010]en
dc.subjectcarbon monoxide oxidationen
dc.subjectmoisture effecten
dc.subjectreaction mechanismen
dc.subjectsupported gold catalysten
dc.subjectTAP studyen
dc.titleTAP study on carbon monoxide oxidation over supported gold catalysts Au/Ti(OH)*4 and Au/Fe(OH)*3: Moisture effecten
dc.typeArticleen
dc.contributor.departmentThe University of Tokyo. Graduate School of Science. Department of Chemistry.en
dc.identifier.journalJournal of Catalysisen
ref.citationcount2 [Scopus, 17/05/2010]en
or.citation.harvardOlea, M., Tada, M. and Iwasawa, Y. (2007) 'TAP study on carbon monoxide oxidation over supported gold catalysts Au/Ti(OH)*4 and Au/Fe(OH)*3: Moisture effect', Journal of Catalysis, 248 (1), pp.60-67.-
All Items in TeesRep are protected by copyright, with all rights reserved, unless otherwise indicated.