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以介孔分子筛SBA-15为载体,采用浸渍法制备了系列四水硫酸锆(ZS)负载型催化剂ZS/SBA-15,用FT-IR、EDS、XRD、N2吸附-脱附、Hammett指示剂等对催化剂的组成、结构和酸强度进行了表征。结果表明,硫酸锆负载后,催化剂仍基本保持六方有序的孔阵列和尺寸不变的介孔孔道;在负载量<40%时,硫酸锆均能在载体上高度分散。该系列催化剂具有中等强度的酸中心,对乙二醇单乙醚与乙酸、正丁醇与柠檬酸的酯化反应有很高的催化活性,且对目标酯产物的选择性为100%。在最佳的负载量和反应条件下,乙二醇单乙醚和柠檬酸的转化率约高达98%,催化剂重复使用多次仍可保持相当的活性。
A series of ZS supported ZS catalysts, ZS / SBA-15, were prepared by impregnation method using mesoporous molecular sieves SBA-15 as support. The catalysts were characterized by FT-IR, EDS, XRD, N2 adsorption-desorption, Hammett indicator The catalyst composition, structure and acid strength were characterized. The results show that the catalyst still retains hexagonal ordered pore arrays and mesopores with unchanged size after zirconium sulphate loading. When the loading is less than 40%, the zirconium sulphate can be highly dispersed on the support. This series of catalysts has a moderate acid site with high catalytic activity for the esterification of ethylene glycol monoethyl ether with acetic acid, n-butanol and citric acid with 100% selectivity to the desired ester product. At the optimal loading and reaction conditions, the conversion of ethylene glycol monoethyl ether and citric acid is up to 98%, and the catalyst can still retain considerable activity after repeated use for several times.