Change search
ReferencesLink to record
Permanent link

Direct link
Production of hydrogen by partial oxidation of methanol over ZnO-supported palladium catalysts prepared by microemulsion technique
KTH, Superseded Departments, Chemical Engineering and Technology.
KTH, Superseded Departments, Chemical Engineering and Technology.
2003 (English)In: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 242, no 2, 233-245 p.Article in journal (Refereed) Published
Abstract [en]

Selective production of hydrogen by partial oxidation of methanol, using air as oxidant, was studied over a series of ZnO-supported Pd catalysts. Microemulsion-assisted synthesis and conventional impregnation techniques were used for preparation of catalysts containing Pd particles of different sizes. Catalyst characterisation included BET, XRD and TEM analyses. The influence of Pd particle size on catalytic activity and product distribution was studied by carrying out activity measurements at temperatures between 230 and 300 degreesC using a stoichiometric feed composition. All catalysts performed well with respect to methanol conversion and hydrogen yield. Both methanol conversion and hydrogen selectivity increased with increasing reaction temperature, the latter at the expense of water formation. Oxygen conversion was complete throughout the examined temperature range. These selectivity trends, with a strong dependence of hydrogen and carbon monoxide selectivities on methanol conversion and reaction temperature, support a reaction scheme consisting of consecutive methanol combustion, steam reforming and decomposition. More importantly, a correlation between Pd particle size and carbon monoxide selectivity was found. When the microemulsion catalysts are compared, carbon monoxide formation increases with increasing particle size. This was not observed over the impregnated reference catalysts, which exhibited high carbon monoxide-levels throughout the examined temperature range. Bimetallic PdZn particles were detected in spent catalysts by means of XRD and it is suggested that the catalytic activity is dependent on the formation of PdZn, the catalytic function being different from that of Pd-0.

Place, publisher, year, edition, pages
2003. Vol. 242, no 2, 233-245 p.
Keyword [en]
fuel cell vehicles, hydrogen production, methanol oxidation (partial), carbon monoxide, Pd/ZnO catalysts, microemulsion technique, PdZn, fuel-cell applications, copper-based catalysts, in-oil microemulsion, selective production, water, kinetics, pd, cu/zno/al2o3, mechanism, gas
URN: urn:nbn:se:kth:diva-22343ISI: 000181680200002OAI: diva2:341041
QC 20100525Available from: 2010-08-10 Created: 2010-08-10Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Järås, Sven G.Boutonnet, Magali
By organisation
Chemical Engineering and Technology
In the same journal
Applied Catalysis A: General

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 56 hits
ReferencesLink to record
Permanent link

Direct link