具有中孔结构的SO_4^(2-)/Zr-HMS型固体超强酸的合成和结构表征

Preparation and Structure Characterization of a Mesoporous Solid Superacid Catalyst SO_4^(2-)/Zr-HMS

用 TEOS-Zr-HAD-H2 O-Ethanol体系合成了 Zr-HMS的中孔分子筛 ,脱除模板剂后用 0 .5 mol/ L硫酸处理和 5 5 0℃高温焙烧 3 h,制得一种中孔 SO2 -4 / Zr-HMS超强酸催化剂 .采用 XRD对其结构进行表征 .用指示剂法、 TG和 NH3-TPD对其酸性进行了表征 .结果表明 ,经过一系列处理后制得的 SO2 -4 / Zr-HMS催化剂具备 HMS中孔分子筛的结构特征 ,其酸强度可达 H0 =-1 3 .75 .在锆及 SO2 -4 含量远远低于 SO2 -4 / Zr O2 的条件下 ,SO2 -4 / Zr-HMS催化剂对于苯酐和正丁醇酯化反应的活性仍高于 SO2 -4 / Zr O2

A mesoporous solid superacid catalyst, SO 2-_4/Zr-HMS, was prepared by sulfating the mesoporous Zr-HMS, which was synthesized from TEOS-zrconium-HDA-H_2O-ethanol system, with aqueous solution of 0.5 mol/L H_2SO_4 followed by calcining at 550 ℃ for 3 h in static air. The structure of catalyst was characterized by XRD, and the acidity of the catalyst was investigated by Hammit indicator method, TG and NH_3-TPD. It is shown that the catalyst SO 2-_4/Zr-HMS possesses the structure of HMS and with the acid strength by -13.75(H_0). The catalytic activity of SO 2-_4/Zr-HMS in the esterification of phthalic anhydride with butanol is higher than that of SO 2-_4/ZrO_2.