Chinese Journal of Catalysis ›› 2017, Vol. 38 ›› Issue (1): 48-57.DOI: 10.1016/S1872-2067(16)62549-4

• Article • Previous Articles     Next Articles

One-step post-synthesis treatment for preparing hydrothermally stable hierarchically porous ZSM-5

Jian Ding, Teng Xue, Haihong Wu, Mingyuan He   

  1. Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
  • Received:2016-08-31 Revised:2016-09-30 Online:2017-01-18 Published:2017-01-18
  • Contact: Haihong Wu,Tel/Fax:+86-21-62238510;E-mail:hhwu@chem.ecnu.edu.cn
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (21403070, 21573073), National Key Technology Research and De-velopment Program (2012BAE05B02), and Shanghai Leading Academic Discipline Project (B409).

Abstract:

Hierarchically porous ZSM-5 (SiO2/Al2O3≈120) containing phosphorus was prepared by a one-step post-synthesis treatment involving controlled desilication and phosphorous modification. The hier-archically porous ZSM-5 featured high thermal and hydrothermal stability. The obtained ZSM-5 zeolites were systematically characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption, NH3 temperature-programmed de-sorption, and 27Al and 31P magic-angle spinning nuclear magnetic resonance spectroscopy. The prepared ZSM-5 displayed enhanced activity and prolonged lifetime toward hydrocarbon cracking. The high activity was attributed to improved coke tolerance owing to the presence of the highly stable mesoporous network of ZSM-5 and acid sites introduced upon phosphorus modification. Additionally a mechanism of the stabilization of the zeolites by phosphorus was proposed and dis-cussed.

Key words: Desilication, Phosphorus stabilization, One-step modification, Hydrothermal stability, Hydrocarbon cracking