Chinese Journal of Catalysis ›› 2012, Vol. 33 ›› Issue (10): 1724-1729.DOI: 10.3724/SP.J.1088.2012.20650

• Research papers • Previous Articles     Next Articles

Synthesis and Growth Mechanism of the Core-Shell SAPO-34/AlPO-18 Molecular Sieves

ZHANG Lin1, TIAN Peng1, SU Xiong1,2, FAN Dong1,2, WANG Dehua1,2, LIU Zhongmin1,*   

  1. 1Dalian National Laboratory for Clean Energy, National Engineering Laboratory for Methanol-to-Olefins, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China; 2Graduate University of Chinese Academy of Sciences, Beijing100049, China
  • Received:2012-06-26 Revised:2012-07-26 Online:2012-09-28 Published:2012-09-28

Abstract: The core-shell molecular sieves comprised of SAPO-34 as core and AlPO-18 as shell were hydrothermally synthesized and characterized by X-ray diffraction, scanning electron microscopy (SEM), and ultra-high resolution field-emission scanning electron microscopy (FE-SEM) techniques. The SEM results show that the growth of the shell AlPO-18 nanocrystals with different orientations and compactness can be controlled by adjustment of the synthesis conditions such as core pretreatment, liquid to solid ratio, and growth number. The ultra-high resolution FE-SEM images confirm that the growth performance of the shell AlPO-18 is closely related to the surface microstructure of SAPO-34, indicating the mechanism that the microstructure on the external surface of the core directs the growth of the shell.

Key words: core-shell molecular sieve, SAPO-34, AlPO-18, growth mechanism, ultra-high resolution field-emission scanning electron microscopy