Abstract
The crystal phases, microstructural features, and local atomic coordination of CuO-Al2O3 catalyst for NOx removal were studied by some experimental techniques. A spinel-like phase, which exhibits short-range structure, appears at around 900°C. Catalytic activity can be maintained at <900°C, but degenerated at >1100°C. The activity of catalyst is controlled by the Cu-containing crystal phase of surface spinel. At low heating temperatures, the diffusion of copper into alumina will be important to surface modification to create active sites. The ESR and XANES results suggest that atomic structures in the interfacial area appear to play an important role in the lean-NOx removal activity.
