Abstract: ZrO₂-Al₂O₃ was prepared by co-precipitation method, SO₄^2-/ZrO₂-Al₂O₃ was prepared by impregnating ZrO₂-Al₂O₃ with sulfuric acid solution, and Pt-SO₄^2-/ZrO₂-Al₂O₃ solid superacid catalyst was prepared by impregnating platinum chloride solution by equal volume method. BET, XRF, XRD, NH₃-TPD, Py-IR techniques were used to characterize the pore structure, crystal phase structure, and acid properties of different Pt- SO₄^2-/ZrO₂-Al₂O₃ catalysts. The n-hexane was used as the probe material to evaluate the conversion and isomerization activity of Pt-SO₄^2-/ZrO₂-Al₂O₃ catalysts. The results showed that when the content of Al₂O₃ was 5%, the roasting temperature of SO₄^2-/ZrO₂-Al₂O₃ was 650 ℃, and the sulfuric acid added was 15%, the tetragonal phase zirconia content of Pt- SO₄^2-/ZrO₂-Al₂O₃ catalyst was the highest, the total acid content and the amount of B acid were the most, and both the conversion and isomerization rate of n-hexane were the highest. At 2.0 MPa, 240 ℃, volumetric space velocity of 1.0 h^-1, and hydrogen-to-oil volume ratio of 700, the conversion of n-hexane on Pt-SO₄^2-/ZrO₂-Al₂O₃ catalyst was 88.72%, the isomerization rate was 80.07%.

Key words: platinum, zirconia, alumina, solid superacid, isomerization, n-hexane