EFFECT OF SILICA SOL TREATMENT OF THE ACID PROPERTIES OF THE ALUMINUM-OXIDE SURFACE

Methods based on the formation of paramagnetic complexes of anthraquinone molecular probes and the stable TANANA nitroxyl radical with Lewis acid sites were used to study the acid properties of the aluminum oxide surface with deposited silica gel. When the SiO2 content is about 10 mass %, the contribution of the acid properties of the aluminum oxide surface is reduced by an order of magnitude. The acid properties of the reformed surface are analogous to those for aluminosilicates. Our results indicate that Al3+ ions diffuse into the silicon-oxygen framework during the preparation process.