Structured zeolites are the potential catalysts for the refinery and petrochemical industry applications.This study aims to develop and investigate the nano-structured zeolite for the hydrocarbon conversion with better hydrothermal stability [1-2].There are several challenges that limited utilizing zeolites in a wider range for cracking applications,including selectivity expectation,stability requirement and high coke formation.In order to overcome these intrinsic limitations,zeolite crystal size was reduced to the nanoscale to shorten the diffusion path as compared with the conventional microsized zeolite,to improve the accessibility of larger molecules on mesoporous surface and to accelerate the reaction rate.Although there have been many zeolite applications based on their microporous structures,this study explores the effect of synthesis parameters on the catalyst activity and the hydrothermal stability of nanoscale MFI zeolites.To develop the hydrophobic zeolites,the fluoride media,and rare earth metals were used as the hydrophobic agent.The synthesized nanocrystal zeolite catalysts were characterized by ammonia temperature programmed desorption(NH3-TPD),XRD,NMR,and N2 physisorption.The hydrocarbon cracking catalytic’testing was carried out by using fixed bed reactor at the space velocity of 2-8 h1 to investigate the conversion,selectivity,reaction stream stability and coking rate with an emphasis to compare the nanostructure and microstructure zeolites.Also,the presentation will discuss the reaction mechanism of shape selectivity of nanocrystal zeolites at moderate temperature and effect of steam addition to the zeolite stability.
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