Effect of morphology and particle size of ZSM-5 on catalytic performance for ethylene conversion and heptane cracking

To determine the effect of morphology and particle size of ZSM-5 (particle type ZSM-5) on catalytic performance (catalytic activity, product distribution, and catalyst lifetime), ZSM-5 with varying particle size and a ZSM-5 nanosheet were prepared to study the conversion of ethylene and cracking of n-heptane. The physicochemical properties were also investigated by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, 29Si MAS, and 27Al 3Q MAS nuclear magnetic resonance.The rate of ethylene conversion was found to increase with decreasing ZSM-5 zeolite particle size, while the product distribution was independent of the particle size and morphology of the catalyst. In n-heptane cracking, the ZSM-5 nanosheet showed lower catalytic activity than particulate ZSM-5, and the distribution of hydrocarbon products was independent of the morphology of ZSM-5. In both reactions, the effects of morphology and particle size on catalytic performance will be discussed.

Graphical abstractFor pore reactions such as ethylene conversion and heptane cracking, the small particle ZSM-5 zeolites are found to be highly active than the large particle and nanosheet ZSM-5.Figure optionsDownload full-size imageDownload high-quality image (63 K)Download as PowerPoint slideHighlights► ZSM-5 zeolites with various particle size and nanosheet ZSM-5 were prepared. ► Product selectivity is independent of particle size and morphology. ► The rate of ethylene conversion increases with decreasing the particle size. ► Nanosheet ZSM-5 shows low activity due to the short residence time. ► Nanosheet and small particle ZSM-5 show high stability.