Direct impregnation method for preparing sulfated zirconia supported on mesoporous silica

A new method has been developed to prepare sulfated zirconia (S-ZrO₂) supported on mesoporous silica. With direct exchange of metal containing precursors for the surfactants in the as-synthesized MCM-41 materials, the problem of fill-up of the mesoporous structure was avoided and high sulfur content was achieved. By using this method, the composite of S-ZrO₂/MCM-41 with ZrO₂ content higher than 60 wt.% can be easily obtained without serious blockage of the pore structure of MCM-41. Nevertheless, the pore size and pore volume of the resultant S-ZrO₂/MCM-41 composites were found to vary markedly with the loading of ZrO₂. The strong acidic character of the obtained composites was examined by using them as catalysts in n-butane isomerization. Introduction of other metals such as aluminum as promoter into S-ZrO₂/MCM-41 can be easily conducted by the direct impregnation method.