NO reduction, CO and hydrocarbon oxidation over combustion synthesized Ag/CeO2 catalyst
The combustion technique produces ionically dispersed Ag on a nano-crystalline CeO2 surface. The catalysts thus produced were characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. Catalytic properties towards NO reduction, CO and hydrocarbon oxidation have been investigated using the temperature programmed reaction technique in a packed bed tubular reactor. These results are compared with α-Al2O3 supported finely divided Ag metal particles synthesized by the same method. Both oxidation and reduction reactions over Ag/CeO2 have been observed to occur at lower temperatures compared to Ag/Al2O3. The rate and turnover frequency of the NO+CO reaction over 1% Ag/CeO2 are 56.3 μmol g−1 s−1 and 0.97 s−1 at 225°C respectively. Activation energy (Ea) values are 71 and 67 kJ mol−1 for CO+O2 and NO+CO reactions, respectively, over 1% Ag/CeO2 catalyst.