Modified seeding method for preparing hierarchical nanocrystalline ZSM-5 catalysts for methanol aromatisation

A series of ZSM-5 nanozeolites with hierarchical porosity were prepared by a seeding method and the addition of phenylaminopropyltrimethoxysilane (PATMOS) into the medial synthesis system. The influence of the amounts of PATMOS on the pore characteristics, crystallinity, morphology and acidity of the ZSM-5 zeolites were studied by XRD, N-2-adsorption, Al-27 MAS NMR, SEM, TEM and NH3-TPD. The crystal size of the ZSM-5 zeolites could be adjusted in a certain range, and the mesopores were generated by introducing PATMOS. In addition, the catalytic performances of the hierarchical nanocrystalline ZSM-5 were investigated for methanol aromatisation (MTA). The hierarchical nanocrystalline ZSM-5 catalysts with a small crystal size and numerous mesopores exhibited high stability for the MTA reaction due to an enhanced mass transfer property and reduced diffusion limitations. (C) 2016 Elsevier Inc. All rights reserved.