Ag-Mordenite catalysts used as a hydrocarbon trap and in the Selective Catalytic Reduction of NOx

ASPROMONTE, SOLEDAD G.; MIRÓ, EDUARDO E.; BOIX, ALICIA V.

Sorrento

Simposio; 16th International Zeolite Conference and 7th International Mesostructured Materials Symposium; 2010

Asociación de Zeolita Internacional (IZA) y la Asociación Internacional de Materiales Mesoestructurados (IMMA), juntos con la Asociación de Zeolita italiana (AIZ) y el Grupo Interdivisional de Catálisis de la Sociedad italiana Química (GIC-SCI)

Ag-NaMOR was prepared with different Ag contents. The TPR and XPS analyses of the used and calcined samples determined the presence of Ag+ ions at exchange positions with the support. The presence of Ag2O particles dispersed in the zeolite structure was also detected. The Agx-M are active and selective catalysts on C4H10-SCR. The selectivity towards N2 increased with the addition of 2% H2O in the feed as a result of the cleaning up effect of water on the catalytic surface. Ag+ ions at exchange positions represent the preferential adsorption site of hydrocarbon at low temperature and allow the retention of toluene to 400°C. The FTIR results of adsorbed toluene show that the latter reacts with the NO/He flow. The bands observed correspond to typical intermediate compounds (surface cyanide, isocyanide and isocyanate species) of the SCR-NOx.