Preparation of new solid superacid catalyst, zirconium sulfate supported on γ-alumina and activity for acid catalysis

Zirconium sulfate supported on γ-Al2O3 catalysts were prepared by impregnation of powdered γ-Al2O3 with zirconium sulfate aqueous solution followed by calcining in air at high temperature. For Zr(SO4)2/γ-Al2O3 samples, no diffraction line of zirconium sulfate was observed up to 50 wt.%, indicating good dispersion of Zr(SO4)2 on the surface of γ-Al2O3. The acidity of catalysts increased in proportion to the zirconium sulfate content up to 40 wt.% of Zr(SO4)2. 40-Zr(SO4)2/γ-Al2O3 calcined at 400 °C exhibited maximum catalytic activities for 2-propanol dehydration and cumene dealkylation. The catalytic activities for both reactions, 2-propanol dehydration and cumene dealkylation were correlated with the acidity of catalysts measured by ammonia chemisorption method.