NO reduction with CO over Pd/gama-Al2O3. The effect of water on the formation of NH3 and the stability of nitrogen-containing surface species

IGNACIO O. COSTILLA; MARÍA A. VOLPE; CARLOS E. GIGOLA

Seoul, Korea

Congreso; 14th International Congress of Catalysis; 2008

The NO + CO reaction has been studied in the absence and presence of H2O over a Pd/g-Al2O3 catalysts at 300oC. Special attention was given to the formation of NH3, surface isocyanate (-NCO) and deposits of CNH-containing species. Gas phase analysis and surface characterization by FTIR spectroscopy revealed that the mentioned products are formed under dry conditions with the participation of surface ¡VOH groups. In the presence of H2O the formation of NH3 is inhibited and the surface deposits are eliminated. This behavior is different from that of Pt/g-Al2O3 where H2 for the undesirable formation of NH3 is mainly provided by the water-gas shift reaction.