Abstract
The influence of the preparation method on the NO–SCR by NH3 activity of Cu-OFF catalysts has been studied on presence of oxygen. The catalysts structure and the nature of copper species have been investigated by XRD, 27Al MAS NMR, UV-visible spectroscopy and H2-TPR. Among the examined preparation methods, the ionic exchange in aqueous solution gives the highest efficient catalyst in NO-SCR. It is shown that Cu cationic species are formed in large extent with this method despite the presence of minor amounts of small oxide clusters.