Sn掺杂MCM-41介孔分子筛的制备、表征及催化性能研究

Preparation,Characterization and Catalytic Properties of Sn-Containing MCM-41

在低模板剂浓度和弱碱介质中合成催化材料Si-MCM-41、Sn-MCM-41,并用XRD、N2物理吸附-脱附、FT-IR、ICP-AES和TEM等手段对催化材料进行了表征.研究了合成方法对制备Sn掺杂MCM-41介孔分子筛的影响,结果表明:水热晶化法(DHT)合成的Sn-MCM-41,Sn物种主要进入分子筛的骨架中;而模板离子交换法(TIE)合成的Sn-MCM-41,Sn物种主要位于分子筛的表面.Sn-MCM-41介孔分子筛催化环己酮Baeyer-Villiger氧化反应结果表明,n(H2O2):n(酮)=3:1,30g1,4-二氧六环为溶剂,H2O2为氧源,70℃反应6h,环己酮的转化率可达40.02%,ε-己内酯的选择性为45.69%.

The molecular sieve catalysis material of Si-MCM-41,Sn-MCM-41 were preparaed under the condition of low template concentration in weak base and the samples were characterized by XRD,N2 adsorption-desorption,FT-IR,ICP-AES and TEM techniques.Effect of the synthesis methods on the Sn-containing MCM-41 were studied.The results showed that Sn species were mainly incorporated into the framework of MCM-41 molecular sieves prepared by direct hydrothermal synthesis method（DHT）,while Sn species were mainly existed on the wall surface of Sn-MCM-41 molecular sieves prepared by template-ion exchange method（TIE）.The catalytic properties of Sn containing MCM-41 molecular sieves in Baeyer-Villiger oxidation of cyclohexanone were investigated.Catalytic activity results show that under the reaction condition of n（H2O2）：n（Cyclohexanone）=3：1,30 g dioxane,at 70℃ for 6 h,the conversion of cyclohexanone and the selectivity of ε-caprolactone reach 40.02% and 45.69%,respectively.