International Journal of Photoenergy
Volume 2008 (2008), Article ID 759736, 7 pages
doi:10.1155/2008/759736
Research Article

A Photocatalytic Active Adsorbent for Gas Cleaning in a Fixed Bed Reactor

Peter Pucher,1 Rabah Azouani,2 Andrei Kanaev,2 and Gernot Krammer3

1Department of Chemical Apparatus Design, Particle Technology and Combustion, Graz University of Technology, Inffeldgasse 25/B, 8010 Graz, Austria
2Laboratoire d'Ingénierie des Matériaux et des Hautes Pressions, CNRS, Institut Galilée, Université Paris-Nord, 93430 Villetaneuse, France
3Department of Energy and Process Engineering, Norwegian University of Science and Technology, Kolbjørn Hejes vei 1, 7491 Trondheim, Norway

Received 24 July 2007; Accepted 27 February 2008

Academic Editor: Russell Howe

Copyright © 2008 Peter Pucher et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Efficient photocatalysis for gas cleaning purposes requires a large accessible, illuminated active surface in a simple and compact reactor. Conventional concepts use powdered catalysts, which are nontransparent. Hence a uniform distribution of light is difficult to be attained. Our approach is based on a coarse granular, UV-A light transparent, and highly porous adsorbent that can be used in a simple fixed bed reactor. A novel sol-gel process with rapid micro mixing is used to coat a porous silica substrate with TiO2-based nanoparticles. The resulting material posses a high adsorption capacity and a photocatalytic activity under UV-A illumination (PCAA = photocatalytic active adsorbent). Its photocatalytic performance was studied on the oxidation of trichloroethylene (TCE) in a fixed bed reactor setup in continuous and discontinuous operation modes. Continuous operation resulted in a higher conversion rate due to less slip while discontinuous operation is superior for a total oxidation to CO2 due to a user-defined longer residence time.