Fabrication of coffin-like multilamellar ZSM-5 monocrystals via bio-renewable surfactant alkyl polyglucoside 1214 and its application in methanol-to-propylene reaction

Abstract

The prevention of deactivation of catalysts is a key issue in catalysis. It is an effective approach to prevent the deactivation of a catalyst by controlling the morphology of the catalyst because special morphology can improve mass transfer rate so that coke precursors can escape from the catalyst rapidly. ZSM-5 is an important catalyst in industry and the synthesis of ZSM-5 nanosheets with a multilamellar or unilamellar structure is an effective approach to prevent the deactivation of this catalyst because this solution greatly shortens diffusion paths. Herein, bio-renewable surfactant alkyl polyglucoside 1214 (APG1214) was used to synthesize ZSM-5 for the first time and coffin-like multilamellar ZSM-5 monocrystals constituted of regularly stacked 2D-sheets (thickness of 30–100 nm) were synthesized with the assistance of APG1214. In order to investigate the role and effect of APG1214 and the mechanism of the formation of this special morphology in detail, various characterizations (XRD, XRF, N2 physisorption, SEM, TEM, NH3-TPD, TGA) were used in this study. Methanol-to-propylene (MTP) reaction was selected as a probe reaction: the lifetime of coffin-like multilamellar ZSM-5 monocrystals was 1.5-fold longer than that of conventional ZSM-5 and the propylene selectivity of coffin-like multilamellar ZSM-5 monocrystals increased by 10 % compared with that of conventional ZSM-5 because 2D-nanosheets provided short diffusion paths. This work provides a green strategy for synthesizing multilamellar ZSM-5 monocrystals.