The effect of Pd-In interactions in a mordenite framework upon NOx SCR with methane

HERNÁN DECOLATTI; FERENC LÓNYI; HANNA SOLT; EDUARDO MIRÓ; LAURA GUTIERREZ

Sorrento

Conferencia; 16th International Zeolite Conference joint with the 7th International Mesostructured Materials Symposium; 2010

The cooperation effect has been reported by Hamada [1] as a suitable way to improve theperformance of catalysts for the NOx reduction with hydrocarbons. In this vein, Kikuchi andcoworkers [2,3] performed several studies on the effect of the addition of precious metals (Pt,Rh and Ir) to In/H-ZSM5. They proposed that a fundamental role of the precious metals is toaccelerate the NO oxidation step even in the presence of water, thus obtaining highly activeand selective solids. On the other hand, it has been reported that the catalytic activity ofindium-containing zeolites is generally attributed to the presence of [InO]+ active sites [2-5],which are the commonly formed species after the oxidative treatment of the ion-exchangedsamples, regardless of the zeolite structure, Si/Al ratio or acidity of the zeolite matrix. In thiswork we study the effect of the addition of palladium to InHMordenite catalysts prepared bythe reductive solid state ion exchange method (RSSIE). We performed the characterization ofsolids by TPR, NO adsorption and FTIR of adsorbed CO in order to understand the differentinteractions between Pd, In and the zeolitic matrix and their effect on the catalytic behavior.