Catalyzed traps for diesel soot abatement: In situ processing and deposition of perovskite catalyst

The present paper deals with the preparation of catalytic filters for Diesel particulate removal by developing an in situ solution combustion synthesis method. Lanthanum chromite perovskite catalyst has been deposited on silicon carbide and cordierite honeycombs with the aim to investigate the influence of the starting solution containing catalyst precursors on the coating characteristics. SEM, XRD and EDX analyses have been carried out in order to evaluate the homogeneity and the thickness of the catalyst layer. In particular, using concentrated solutions, a single combustion synthesis step was found to be sufficient to obtain a continuous catalyst film on the support. Pressure drop evaluations and adhesion tests have also been performed thus verifying the possibility to insert this kind of catalyzed traps on the diesel exhaust gas lines. The homogeneity and the high adherence of the deposited catalyst layer, as well as the simplicity and the rapidity of the method, prove its suitability for immediate technological applications. (c) 2005 Elsevier B.V. All rights reserved.