Beta zeolites were successfully synthesized via hydrothermal method using sodium aluminate as aluminium source, silica sol ( Ludox) as silicon source and TEAOH as template, respectively. The effects of different additives polyvinyl pyrrolidone ( PVP) and Methyltriethoxysilane ( MTS) on their structural properties and synthesis mechanism were investigated in detail by various characterizations, such as XRD, TEM, BET, ICP, 29 Si-NMR and NH3-TPD method. Also, their catalytic performances were evaluated through catalytic cracking of cumene. The results showed that the beta zeolite obtained in the PVP-added system presented a better crystallinity, higher Si/Al molar ratio (25. 68), and larger surface area (772 m2/g). Comparably, the MTS-effected samples revealed a larger surface area (657 m2/g), higher Si/Al molar ratio (25. 76), but lower crystallinity and smaller particle sizes( around 160-320 nm) . Moreover, both of them exhibited a good catalytic activity for cumene cracking due to the existences of abundant and strong acid content.%分别以铝酸钠和硅溶胶为铝源和硅源,四乙基氢氧化铵为模板剂,在水热条件下,考察了添加剂(聚乙烯吡咯烷酮(PVP)和甲基三乙氧基硅烷(MTS))对合成Beta分子筛结构与性能的影响,并通过XRD、TEM、BET、ICP、29 Si-NMR和NH3-TPD等方法对合成样品进行了结构表征和作用机理讨论,同时以催化裂化异丙苯为模型反应评价其催化性能.结果表明,与传统Beta分子筛相比,加入PVP后所得样品具有更高结晶度和较高的硅铝物质的量比(25.68)以及较大的比表面积(772 m2/g);而加入MTS后尽管具有较大比表面积(657 m2/g)和较高硅铝物质的量比(25.76),但是结晶度却相对降低,且粒径减小(160-320 nm).两种添加剂作用下所得样品均具有更多酸量,在催化裂化异丙苯的反应中表现出较高的催化活性.
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