Abstract:

ZSM-34 with different sizes was synthesized successfully employing choline chloride as a template under crystallization conditions of single-stage, two-stage, two-stage with the help of seed, respectively. The products were characterized by X-ray diffraction, scanning electron microscopy, N2 adsorption/desorption, NH3-temperature programmed desorption and NMR techniques. The results show that two-stage crystallization has advantages in shorter crystallization time from 96h to 72 h, while the two-stage crystallization with the help of seed appears much more outstanding, the crystallization process is finished after only 24 h. The crystallization curve analysis indicates that two-stage crystallization with the help of seed is helpful to rapidly synthesize ZSM–34 with having stable properties.

Key words: crystallization conditions, ZSM-34, hydrothermal synthesis, characterization, crystallization process