ABSTRACT CTS-9522066 This project explores the use of sol-gel preparation of mixed oxides to achieve predictable structures or textures and to apply this to the synthesis of acid catalysts. Specifically, titania-silica and alumina-silica are studied; the silicon precursor has significantly slower reactivity and this permits prehydrolysis to be used as a tuning variable. By varying the prehydrolysis ratio, gel networks of various microstructures can be obtained. Characterization of the product properties may provide a correlation of homogeneity with acidity. Nitrogen adsorption, X-ray diffraction, thermal analysis, pyridine adsorption, and 1-butene isomerization are used to characterize the textural, structural, and catalytic properties of the mixed oxides. Alternative precursors such as double metal alkoxides and performed sols are also studied, as are mixed oxides prepared by coprecipitation. This effort should provide the means to design mixed oxides with specific properties. Although the procedures to be used are well established, little systematic work on how the variables involved affect product properties has been done. (In other words, mixed oxide preparation is more "art" than "science".) Although this effort looks at catalytic properties, if successful it would clearly be extendable to other applications using mixed oxides, such as optical waveguides. ***
