The Research Of Supported Gold Catalysts For The Oxidation Of Low-concentration Benzene At Low Temperature

A series of supported gold catalysts were prepared by subsequently impregnation of alumina with ferric oxide as washcoat and gold as active component. Some secondary active components including La, Ce and Pt were added to improve the activity of catalysts. These gold catalysts were studied with respect to their catalytic activity for the oxidation of the low-concentration benzene and CO at low temperature. Moreover, the means of SEM, TEM, XRD, DTA and DTG were used to characterize these catalysts and the factors affecting the activity of catalysts were discussed. As a conclusion, a sort of impregnated gold catalysts,Au- Fe203/Al20, catalyst(1 5wt%Fe,0.4wt% Au, reduction at I OOt for 4h)which obtained 90% conversion of benzene at 382C, exhibit the hig.hest activity in all congeneric catalysts. The secondary components, especially Pt, were effective in promoting the activity of catalysts. SEM and TEM photograph showed that these secondary components were able to improve the dispersion of gold cluster, which proved that the dispersion of gold cluster was a main factor that could affect the activity of catalyst.