PREPARATION OF STRONG ACID CATALYSTS BY SULFATE TREATMENT OF CALCINED BOEHMITE

Solid acid catalysts with acid strength of -14.52 < H-0 < -8.2 were prepared by sulfate treatment of the samples of boehmite calcined at 105 - 800-degrees-C. Two preparation methods were used: impregnation of the calcined boehmile with 3.5M H2SO4 or mixing of the boehmite samples with anhydrous aluminum sulfate, in both cases followed by calcination in nitrogen at 650-degrees-C. The catalysts were characterized by measurements of surface area, adsorption of pyridine and benzene, acid strength measurements by the indicator method and by catalytic activity tests in the isomerisation of cyclohexene, p-xylene and n-hexane. Properties of the catalysts prepared by both methods were comparable.