NOx Removal by storage-reduction with propene

Abstract

Nox, which consist of No and No2, are air pollutants. They affect the environment and human health. The major surce of NOx is fossil fuel combustion in power plants and engines. In this work, the catalytic reduction of NOx with propene in the presence of oxygen was carried out over Au/Al2O3 and Au/Ba/Al2O3 catalysts prepared by impregnation and sol-gel methods. Au and Ba loadings were varied in the range 0.5-1% and 5-15%, respectively. The catalysts were characterized by BET, XRD, and AAS. It was found that 0.7% Au impregnated on an Al2O3 sol-gel support and 0.7% Au impregnated on a 5% Ba/Al2O3 sol-gel support showed the best activity at 475 and 500 C, respectively. The percentage of Au loading had no significant effect on catalytic activity while the percentage of Ba loading showed a significant effect. The catalytic activity decreased with increasing percentage of Ba loading. The sequence of Au and Ba impregnation was also investigated. The results showed that it had only a slight effect on catalytic activity. The presence of water vapor had no effect on the activity of both Au/Al2O3 and Au/Ba/Al2O3 catalysts.