类固相法合成具有片状形貌的ZSM-5分子筛

采用类固相合成法，在H2O/SiO2摩尔比为0.5~1.0的条件下，采用高压喷雾混合技术，合成了具有片状结构形貌的ZSM-5分子筛，解决了类固相合成体系中，由于水含量较低，固、液两相混合不均匀的问题。结果表明，在形貌方面，ZSM-5分子筛晶粒形状不规则，表面粗糙，具有片层结构形貌；在孔结构方面，ZSM-5分子筛比表面积为405 m2/g，孔体积为0.37 cm3/g，具有多级孔分布的特点。研究了合成条件对ZSM-5分子筛性能的影响，Na2O/SiO2摩尔比为0.03~0.13时均能合成出ZSM-5分子筛，当复合表面活性剂P与SiO2摩尔比为0.036、晶化时间为20 h时，ZSM-5分子筛结晶度最高达到112 %。研究了晶化过程中水的作用，水主要以水蒸气形态存在，水蒸气主要起到传热作用。合成的ZSM-5分子筛具有较好的柴油加氢异构降凝性能，当柴油凝点降至-35 ℃时，柴油收率达到95.50 %，具有较高的柴油收率，同时产品性质较好。

SYNTHESIS OF ZSM-5 WITH LAMELLAR MORPHOLOGY BY SOLID-LIKE PHASE METHOD

ZSM-5 zeolite with lamellar morphology was synthesized by solid-like phase method at H2O/SiO2 molar ratio of 0.5-1.0. The uniform mixing for solid and solution was realized using high pressure spray-adsorption method and the influence of the synthetic conditions on the properties of prepared ZSM-5 were investigated as well. This synthetic method solved the problem in low water content system where the solid and liquid were hard to mix uniformly. The results show that the ZSM-5 grain is in the form of irregular, rough and lamellar morphology. The synthesized ZSM-5 with a hierarchical pore structure has a surface area 405 m2/g and a pore volume of 0.37 cm3/g. The ZSM-5 can be synthesized in the 0.03-0.13 Na2O/SiO2 ratio range. The crystallinity reaches to 112% at the P/SiO2 ratio of 0.036 and the crystallization time of 20 h. It is found that water is in the form of vapor and has a function of heat transfer during the synthesis process. The synthesized ZSM-5 has an outstanding hydroisomerization performance for diesel isodewaxing. The diesel yield reaches to 95.50 % with a condensation point of -35 ℃.