静态条件下合成纳米片层ZSM-5分子筛

采用具有双功能导向作用的长碳链双季铵盐作为模板剂,原料配比为n(Na_2O)∶n(Al_2O_3)∶n(SiO_2)∶n(C_(22-6)-6Br_2)∶n(H_2SO_4)∶n(H_2O)=30∶1∶100∶10∶18∶4 000,静态条件下合成有序纳米片层ZSM-5分子筛,并采用XRD、N2吸附-脱附、SEM和TEM等对其进行表征。研究部分晶化条件对合成过程的影响。结果表明,增大填充度至50%,可以提高晶化压强,从而提高分子筛结晶度;随着凝胶碱度的增加,纳米片层分子筛结晶度先增大后降低,多片层有序性也发生同样变化;晶化时间对合成过程的前期影响较大,晶化时间6天,分子筛达到较高结晶度,样品形貌均一,介孔孔径分布集中。

Synthesis of ZSM-5 zeolite nanosheets under static conditions

Ordered ZSM-5 zeolite nanosheets were synthesized successfully under static conditions with molar composition of 30Na₂O∶1Al₂O₃∶100SiO₂∶10C_22-6-6Br₂∶18H₂SO₄∶4000H₂O,using long-chain dual-quaternary ammonium salt with dual-function orientation as template agent.The zeolite sample was characterized by XRD,N₂ adsorption-desorption,SEM and TEM.Effects of partial crystallization conditions on synthesis process were explored.The results showed that crystallinity of zeolite improved when filling degree increased to 50%.With increasing of alkalinity of the gel,crystallinity of zeolite increased first and then decreased,and orderliness of multiple nanosheets changed synchronously.Crystallization time had great influence on synthesis in early stage.When crystallization time was 6 days,the sample reached high degree of crystallinity.Morphology was uniform and mesoporous pore size distribution was centralized.