Synthesis of SAPO5 molecular sieve microspheres through microwave hydrothermal method and it′s formation mechanism
GAO Junping1, 2, LU Lihua2, CHEN Yashao1*, DONG Tao1, WANG Taishan1
(1 Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; College of Chemistry and Materials Science, Shaanxi Normal University, Xi′an 710062, Shaanxi, China; 2 Chemistry Department of College, Pharmacy of the Fourth Military Medical University, Xi′an 710032, Shaanxi, China)
Abstract:
SAPO5 molecular sieve microspheres and its microcrystal were synthesized with TEA as template using microwave hydrothermal technique. Influence of the template on the shape and surface structure of SAPO5 molecular sieve was investigated. The molecular sieves were characterized with Xray diffraction spectroscopy (XRD) and scanning electron microscopy (SEM). The results showed that the SAPO5 molecular sieve had AFItype crystalline structure, high crystallinity and six prism microcrystal, and the microspheres composed of SAPO5 microcrystals possess high crystallinity and good integrity. The dosage of TEA greatly affected the surface structure and the assembling behaviors of SAPO5 molecular sieve. In presence of high dosage of TEA, the SAPO5 molecular sieve microcrystals were formed. Under the low dosage of TEA, the SAPO5 molecular sieve microspheres with integrity surface could be obtained. The proposed formation mechanism indicates that TEA acts not only as structuredirected agent (SDA) for the synthesis of SAPO5 molecular sieve but also as the control agent for formation of microspheres with hierarchical structure.
KeyWords:
SAPO5 molecular sieve; synthesis microwave hydrothermal; SAPO5 microsphere
