柠檬酸溶液处理对β沸石结构性质及烷基化性能的影响

Zeolite beta is a large-pore crystalline aluminosilicate, which was first synthesized by Wadlinger et al[1] in 1967. Due to its peculiar framework topology and suitable acidity, zeolite beta has received increasing industrial interest for some important reactions such as alkylation of benzene with light olefins[2] and alkylation of isobutane with butene[3]. Many literature papers have reported methods to modify the acidity of zeolite beta, which include ion-exchange, hydrothermal treatment, and acid treatment.     

基底表面性质与前驱液化学环境对原位定向构筑钛硅分子筛膜的影响

b取向MFI型分子筛膜能够显著促进分子的传输效率, 被广泛应用于混合物分离及催化领域. 虽然传统的原位水热晶化法已较为成熟, 然而仍难以调控膜层的b轴取向生长. 本文以304不锈钢片为基底, 采用经典的原位水热晶化法研究了基底表面物化性质、 前驱液配比及晶化条件对钛硅分子筛膜b轴取向生长的影响. 结果表明, TiO₂中间层表面的羟基能够定向诱导分子筛晶粒的吸附, 进而提高钛硅分子筛膜的b轴取向程度. 同时, 前驱液中模板剂和水含量对晶粒的大小及膜层的定向生长具有显著影响, 即仅在合适的碱度下才能形成高b轴取向的钛硅分子筛膜.