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以正丙醇锆为锆前躯体,硫酸铵为硫源,十六烷基三甲基溴化铵(CTAB)为模板剂,溴化钾为添加剂,按n(Zr4+)∶n(CTAB)∶n(SO24-)=2∶1∶2,在水热条件、酸性介质中合成了介孔ZrO2/SO24-。通过X射线衍射(XRD),N2物理吸附,扫描电镜(SEM),FTIR分析手段对其结构进行了表征;并以乙酸正丁酯的酯化反应为探针反应,考察了其催化活性。结果表明,采用两步焙烧法去除模板剂后,该样品的介孔结构类似于MCM-41,d值为3.85nm;在500℃焙烧后,该样品仍具有274m2/g的比表面积及3.2nm的平均孔径;SEM显示焙烧后的样品形貌为球形颗粒;FTIR分析得出,焙烧产物ZrO2/SO42-中S=O键对Zr4+有强的吸电子作用,产生强的Lewis酸中心。当催化剂用量为正丁醇质量的2.5%,n(乙酸)∶n(正丁醇)=1∶2,反应3h后,乙酸的转化率达91.48%。
Zirconium n-propoxide as zircon precursor, ammonium sulfate as sulfur source, cetyltrimethylammonium bromide (CTAB) as templating agent and potassium bromide as additive, according to n (Zr4 +): n (CTAB) n (SO24 -) = 2:1:2. Mesoporous ZrO2 / SO24- was synthesized under hydrothermal conditions and in acidic medium. Its structure was characterized by X-ray diffraction (XRD), N2 physical adsorption, scanning electron microscopy (SEM) and FTIR analysis. The esterification reaction of n-butyl acetate was used as the probe reaction to investigate the catalytic activity. The results showed that the mesoporous structure of MCM-41 was similar to that of MCM-41 after removing the template by two-step calcination. The d value was 3.85nm. After calcination at 500 ℃, the sample still had a specific surface area of 274m2 / g and 3.2nm . The SEM results showed that the morphology of the sample was spherical. The FTIR analysis showed that the S = O bond in ZrO2 / SO42- had a strong electron-withdrawing effect on Zr4 +, resulting in strong Lewis acid sites. When the amount of catalyst is n-butanol 2.5%, n (acetic acid): n (n-butanol) = 1: 2, after 3h, the conversion of acetic acid reached 91.48%.