WO₃/CeO₂/TiO₂ Catalysts for Selective Catalytic Reduction of NOx by NH₃: Effect of the Synthesis Method
Katarzyna A. Michalow-Mauke,
Ye Lu,
Davide Ferri,
Thomas Graule,
Kazimierz Kowalski,
Martin Elsener,
Oliver Kröcher
Affiliations
Katarzyna A. Michalow-Mauke
Paul Scherrer Institute, CH-5232 Villigen, Switzerland. [email protected]
Ye Lu
Lab. for Solid State Chemistry and Catalysis, Empa Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
Davide Ferri
Paul Scherrer Institute, CH-5232 Villigen, Switzerland
Thomas Graule
Lab. for High Performance Ceramics, Empa Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
Kazimierz Kowalski
Faculty of Metals Engineering & Industrial Computer Science, AGH University of Science & Technology, Al. Mickiewicza 30, PL-30059 Krakow, Poland
Martin Elsener
Paul Scherrer Institute, CH-5232 Villigen, Switzerland
Oliver Kröcher
Paul Scherrer Institute, CH-5232 Villigen, Institute of Chemical Sciences and Engineering, EPF Lausanne, Switzerland. [email protected]
WO3/CeO2/TiO2, CeO2/TiO2 and WO3/TiO2 catalysts were prepared by wet impregnation. CeO2/TiO2 and WO3/TiO2 showed activity towards the selective catalytic reduction (SCR) of NOx by NH3, which was significantly improved by subsequent impregnation of CeO2/TiO2 with WO3. Catalytic performance, NH3 oxidation and NH3 temperature programmed desorption of wet-impregnated WO3/CeO2/TiO2 were compared to those of a flame-made counterpart. The flame-made catalyst exhibits a peculiar arrangement of W-Ce-Ti-oxides that makes it very active for NH3-SCR. Catalysts prepared by wet impregnation with the aim to mimic the structure of the flame-made catalyst were not able to fully reproduce its activity. The differences in the catalytic performance between the investigated catalysts were related to their structural properties and the different interaction of the catalyst components.
