Formulation of zeolite-mesoporous silica composite catalysts for light olefin production from catalytic cracking  

作　　者：Hassan Alhassawi Edidiong Asuquo Shima Zainal Yuxin Zhang Abdullah Alhelali Zhipeng Qie Christopher M.A.Parlett Carmine D’Agostino Xiaolei Fan Arthur A.Garforth 

机构地区：[1]Department of Chemical Engineering,School of Engineering,The University of Manchester,Manchester M139PL,UK [2]Faculty of Environment and Life,Beijing University of Technology,Beijing 100124,China [3]Diamond Light Source Harwell Science and Innovation Campus,Oxfordshire OX110DE,UK [4]University of Manchester at Harwell,Diamond Light Source Harwell Science and Innovation Campus,Oxfordshire OX110DE,UK [5]UK Catalysis Hub,Research Complex at Harwell,Rutherford Appleton Laboratory,Oxfordshire OX110FA,UK

出　　处：《Frontiers of Chemical Science and Engineering》2024年第11期335-346,共12页化学科学与工程前沿（英文版）

基　　金：China Scholarship Council for his PhD secondment at The University of Manchester(CSC file No.201906120207).

摘　　要：Framework materials such as zeolites and mesoporous silicas are commonly used for many applications,especially catalysis and separation.Here zeolite-mesoporous silica composite catalysts(employing zeolite Y,ZSM-5,KIT-6,SBA-15 and MCM-41 mesoporous silica)were prepared(with different weight percent of zeolite Y and ZSM-5)and assessed for catalytic cracking(using n-heptane,as the model compound at 550°C)with the aim to improve the selectivity/yield of light olefins of ethylene and propylene from n-heptane.Physicochemical properties of the parent zeolites and the prepared composites were characterized comprehensively using several techniques including X-ray diffraction,nitrogen physisorption,scanning electron microscopy,fourier transform infrared spectroscopy,pulsed-field gradient nuclear magnetic resonance and thermogravimetric analysis.Catalytic cracking results showed that the ZY/ZSM-5/KIT-6 composite(20:20:60 wt%)achieved a high n-heptane conversion of 85%with approximately 6%selectivity to ethylene/propylene.In contrast,the ZY/ZSM-5/SBA-15 composite achieved a higher conversion of 95%and an ethylene/propylene ratio of 8%,indicating a more efficient process in terms of both conversion and selectivity.Magnetic resonance relaxation analysis of the ZY/ZSM-5/KIT-6(20:20:60)catalyst confirmed a micro-mesoporous environment that influences n-heptane diffusion and mass transfer.As zeolite Y and ZSM-5 have micropores,n-heptane can move and undergo hydrogen transfer reactions,whereas KIT-6 has mesopores that facilitate n-heptane’s accessibility to the active sites of zeolite Y and ZSM-5.

关 键 词：zeolites mesoporous silica composite catalysts catalytic cracking light olefins 

分 类 号：TQ221.21[化学工程—有机化工] O643.36[理学—物理化学]