铈改性SBA-15介孔分子筛的合成及催化性能

Synthesis and Catalytic Activity of SBA-15 Mesoporous Silica Modified by Cerium

利用浸渍法制备了铈改性的介孔材料Ce-SO42--SBA-15,采用XRD、红外光谱和N2吸附-脱附测定等手段对样品进行了表征。结果表明,制得的复合材料保持载体SBA-15高度有序的介孔二维六角孔道结构。用Hammett指示剂法测定了改性介孔材料表面pH为1.8,属于固体酸。用0.1mol/L的硫酸高铈浸渍SBA-15,焙烧温度为300℃,焙烧时间3h,通过乙酸正丁酯的合成反应考察催化剂Ce-SBA-15的制备,酯化率为95.7%。

Mesoporous silica molecular sieve Ce-SO^2-1-SBA 15 was synthesized via incipient-wetness impregnation. Characterization was done by X-ray diffraction （XRD）, IR spectroscopic, nitrogen adsorption techniques . The results show that cerium has been incorporated into SBA 15 molecular sieve. The prepared materials keep the highly ordered mesoporous two-dimensional hexagonal structure and themesoporous channel structure. The acid strength （pH=1.8 ） on catalyst surface was determined by mean of Hammett indication method, and attribute to solid acid. The catalyst prepared by impregnating SBA-15 in solution of 0.1mol/L. ceric sulfate and being calcined at 300℃ for 3 h showcd best catalytic activity in synthesis of n-butyl acetate. The yield of n-butyl acetate was up 95.7% under the optimum conditions.