Chinese Journal of Catalysis ›› 2020, Vol. 41 ›› Issue (7): 1062-1066.DOI: 10.1016/S1872-2067(20)63545-8

• Communications • Previous Articles     Next Articles

Controllable direct-syntheses of delaminated MWW-type zeolites

Zhendong Wanga,b, Magdalena O. Cichockac, Yi Luoa,c, Bin Zhanga, Hongmin Suna, Yi Tangb, Weimin Yanga   

  1. a State Key Laboratory of Green Chemical Engineering and Industrial Catalysis, Sinopec Shanghai Research Institute of Petrochemical Technology, Shanghai 201208, China;
    b Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials and Laboratory of Advanced Materials Institution, Fudan University, Shanghai 200438, China;
    c Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91, Stockholm, Sweden
  • Received:2019-09-30 Online:2020-07-18 Published:2020-04-18
  • Supported by:
    This work was supported by the National Key R&D Program of China (2017YFB0702800, 2018YFA0209402), the National Natural Science Foundation of China (21503280, 21972168), and the Knut and Alice Wallenberg Foundation (3DEM-NATUR).

Abstract: A method for the direct syntheses of partially and fully delaminated MWW zeolites is reported herein. Two organic amines were introduced into the hydrothermal synthetic system: hexamethyleneimine (HMI), which acted as the structure-directing agent for the MWW layered structure; and dicyclohexylamine (DCHA), in the role of an in-situ delaminating agent. By varying the amount of DCHA, partially and fully delaminated MWW zeolites having two MWW structure layers and one single layer, respectively, were obtained. These were denoted as SCM-1 (Sinopec Composite Material) and SCM-6, respectively. The delaminated materials possess ultra-large external surface areas, and the transmission electron microscopy images illustrated their layered nature. In the reaction of liquid phase benzene alkylation with ethylene, SCM-1, the double-layered MWW zeolite, exhibited far superior catalytic performance compared to zeolite MCM-22.

Key words: Zeolite, MWW, Alkylation, Ethylbenzene, Delamination, Catalysis