| With Green Chemistry being advocated, solid acid catalysts, which protect environment and improve economic efficiency, needs to be applied in the practically chemical industry. Solid acid SO42-/ZrO2 (SZ) has become the concern in catalysis field because of its strong acidity and the advantages over the liquid acid, but its surface area is lower and the catalyst is easily deactivated, seriously limited its application in catalytic reactions. This paper seeks to modify the SZ to synthesize a novel mesoporous solid superacid materials, combining the porous structure of mesoporous molecular sieves with acid properties of superacids.In the paper, mesoporous solid acid sulfated zirconia were prepared by hydrothermal method in acidic medium with one-pot synthesis, using Zr(O-nPr)4 as zirconium precursor, ammonium sulfate as sulfur source, CTAB as template. The structure and properties of catalysts were characterized with XRD, N2 adsorption-desorption, SEM and FT-IR. The isotherms belong to type IV profiles, BET surface area of mesoporous SZ was 274 m2·g-1 more than traditional SZ with 110 m2·g-1, and an average pore diameter of 3.2 nm; The small-angle XRD displayed that low-angle region had a strong diffraction peaks in the 20=2.3°, indicating pore structure with long-range order; The SEM showed morphology of the samples spherical particles; The bands around 1042,1097,1127 and 1230 cm-1 revealed that the catalyst surface SO42- chelated by a bidentate ligand structure together with carrier. The liquid phase esterification of acetic acid and 1-butanol was taken as the probe reaction for the catalyst activity evaluation. The result indicated that optimal conditions for esterification:the amount of catalyst was 3.0% of the mass of n-butanol, the molar ratio of acetic acid to n-butanol was 1:2, and the reaction time was 3h and reaction temperature was 110～115℃, the esterification efficiency was about 96%; After reused five times, the esterification rate can reach 94.6% through regeneration. KIT-6 mesoporous molecular sieves were prepared by hydrothermal method using tetraethoxysilane as silicon source, triblock copolymer Pluronic P123 as template and n-butanol as additive; then using two different ways to load ZrO2, one is impregnation method with zirconium nitrate solution, the other is the urea hydrolysis precipitation method, the mesoporous solid acid SO42-/ZrO2-KIT-6 (SZ-KIT-6) were successfully synthesized, respectively. By studying the influence of preparation conditions on the catalytic properties, we had educed SZ-KIT-6 catalytic best preparative conditions:the ZrO2 loading Factor was 30%, concentration of sulfuric acid impregnating solutions was 0.5 mol·L-1 and impregnation time was 3h, calcination temperature was 600℃. The samples were characterized by XRD, N2 adsorption-desorption, TEM, FT-IR and NH3-TPD methods. The resulting SZ-KIT-6 displayed Ia3d cubic symmetry; TEM revealed that catalyst active component SZ had been scattered KIT-6 on the part of the pore passage and partly deposited on the surface of carrier, but the mesoporous SZ-KIT-6 still had a specific surface area of 451 m2·g-1,0.48 cm3·g-1 pore volume and the most probable pore diameter of 6.46 nm.The catalyst SO42-/ZrO2-KIT-6 was applied in synthesis of dibutyl phthalate. The result indicated that optimal conditions for esterification:the amount of catalyst was 3.5% of the total mass of reactants, the molar ratio of n-butanol to phthalic anhydride was 2.5:1, and the reaction time was 3h and reaction temperature was 120～130℃, in order to test the stability, made the experiment repeatedly, the esterification efficiency was about 93.9%.
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