Structure of vanadium oxide supported on mesoporous carbon-coated monoliths and relationship with its catalytic performance in the SCR of NO at low temperatures

A novel monolithic catalyst based on vanadium supported on mesoporous carbon has been prepared. Vanadium has been supported on carbon-coated monoliths with four different loadings, viz. 3, 4, 6, and 8 wt%. The structure of vanadium catalyst has been characterized by atomic force microscopy (AFM), N-2 adsorption, and XRD. All these techniques indicate that vanadium is dispersed as overlayers up to 6 wt% loadings. For higher loadings crystallites appear. The size of these crystallites (12 nm average height) has been characterized by AFM. The catalysts prepared have been tested in the SCR of NO at low temperatures (363-453 K). Similar activities and selectivities to N-2 were found up to monolayer coverage. Above monolayer coverage activity and selectivity diminish dramatically. The catalysts prepared here show activity and selectivity comparable to those of the most active catalysts reported in the literature. Furthermore, the monolithic shape endows it with significant advantages over the fixed bed. (C) 2004 Elsevier Inc. All rights reserved.