β沸石的合成

Synthesis of Zeolite β

采用水热法 ,在 Na2 O-Si O2 -Al2 O3 -TEAOH-H2 O体系中合成 β沸石 ,研究了各种因素(硅铝比、碱度、水含量、铵浓度、钠含量等 )对晶化过程和产物性质的影响 .XRD法测定物相、相对结晶度及结构参数 ,ICP法分析组成 .给出了合成 β沸石适宜的反应配料组成范围 ,得到其表观成核活化能和晶化活化能分别为 5 0 k J·m ol-1和 1 0 1 k J· mol-1。

Zeolite β was synthesized by hydrothermal method in the system of Na 2O SiO 2 Al 2O 3 TEAOH H 2O.The effects of SiO 2/Al 2O 3 ratios and concentration of some reactants in the raw gel on the product′s crystallization process and properties were investigated.The relative crystallinity,cell parameter were characterized by XRD and ICP,respectively.The results shown,the lower initial SiO 2/Al 2O 3 ratio,the higher utilization ratio of Si;SiO 2/Al 2O 3 ratio mainly affects induction period within crystallization procfess;no zeolite β can be made in an aluminium free system;optimum values for various factors are required for efficient synthesis of zeolite β .The apparent activation eneries for nucleation and crystallization are 50 kJ·mol -1 and 101 kJ·mol -1 ,respectively,the nucleation and crystal growth process which correspond to total alkalinity in the system are all two series reactions.