The Pt-bearing SO42-/ZrO2 superacid catalysts supported on ultra stable Y (USY) zeolite were prepared by impregnation and characterized by X-ray diffracti on, nitrogen adsorption and Hammett indicators. Their catalytic activities were evaluated in the hydroisomerization of n-heptane with an atmospheric fixed-bed r eactor. The catalysts possessed a high surface area, superacidity and well maint ained pore structure of USY support. The supported catalysts with a suitable SO4 2-/ZrO2 loading exhibited a higher catalytic activity and selectivity than the u nsupported SO42-/ZrO2 catalyst or the Pt supported on USY catalyst without super acid. At the reaction temperature of 220 ℃, over the catalyst with a Pt loading of 0.8wt% and ZrO2 loading of 10wt%, the conversion of n-heptane could be as hi gh as 35.2% with a selectivity of 87.9% for isomerization products.
