Monolayer dispersion of oxides and salts on surface of ZrO2 and its application in preparation of ZrO2-supported catalysts with high surface areas

The thermostability of ZrO₂ can be improved by dispersing a layer of an active component onto its surface in advance. The research results of seven kinds of catalysts (ZrO₂-supported MoO₃, WO₃, CuO, SO₄ ^2-, NiO, FeSO₄ and Fe₂O₃) show that the surface areas of the samples prepared by impregnating Zr(OH)₄ with the active components and then calcining at high temperature are much larger than those of the samples prepared with an ordinary method, namely, impregnating ZrO₂ calcined at high temperature. The surface areas of the ZrO₂-supported catalysts obtained in this way are several times that of pure ZrO₂ calcined at the same temperature. The characteristic results show: (1) the active components are dispersed on the surface of ZrO₂ as monolayer; (2) there is a good corresponding relationship between the surface coverage and the surface area of the sample; (3) as the loading of an active component comes up to its utmost dispersion capacity, the surface area of the sample will be the largest. The mechanism responsible for these phenomena has been discussed. This revised version was published online in July 2006 with corrections to the Cover Date.