Cu-ZSM-5 zeolite highly active in reduction of NO with decane -: Effect of zeolite structural parameters on the catalyst performance

The effect of framework aluminum content and local density on the NO(x) reduction with decane under lean burn conditions, i.e. in high excess of oxygen and water vapor (12%) over Cu-ZSM-5 zeolites with various Cu/Al and SUM ratios was investigated. The concentration of "Al pairs" located in one ring and balanced by divalent cations was estimated using divalent cobalt ions as probes. The portion of Cu ions located in vicinity of "Al pairs" or adjacent to a single framework AlO(2)(-) entity was monitored by vis-NIR spectra Of Cu(2+) ions. The most active and stable Cu ions in C(10)H(22)-SCR-NO(x) under lean burn conditions appeared to be those located in vicinity of two Al atoms in one ring coordinated the cation. (c) 2005 Elsevier B.V. All rights reserved.