Surface Acidity of Silica-Alumina Catalysts in Relation to the Preparation Variables

Factorial and rotational designs have been used to analyse the effect of each preparative variable on the surface acid strength distribution in silica-alumina catalysts. Relationships between the surface acidities at pKa= 2·8, 3·3 and 4·8 and the most important variables, namely precipitation rate and temperature, drying pressure and temperature, impregnation concentration and calcination temperature have been obtained.