Abstract:
The selective catalytic reduction of NO with propene in the presence of oxygen was studied over silver supported on alumina catalysts. The catalysts were prepared by sol-gel method. In this study the silver loading was varied in the range of 0, 1.0, 2.0, 4.0, 5.0, 6.0, and 10.0% in order to clarify the effect of metal loading. From the results, the 5% Ag/Al₂O₃ is much more effective at lean NO reduction than other silver loading catalysts and the best reaction temperature is 450 °C. For the study of the promoting effect of oxygen on the rate of the NO reduction, it was found that the conversion of NO to N₂ over Ag/Al₂O₃ catalyst increased as the concentration of oxygen increased from 5 to 20 vol%. The study of the two different function (reduction and oxidation) catalysts was also performed by mixing Ag/Al₂O₃ and Mn₂O₃ physically. The oxidation catalyst, manganese oxide (Mn₂O₃), was obtained by thermal decomposition of manganese precipitate prepared from precipitation method. It was found that Mn₂O₃ catalyst exhibited the negative effect on the conversion of NO to N₂.
