AUTHOR=Wei Qiang , Zhang Pengfei , Liu Xiaodong , Huang Wenbin , Fan Xiayun , Yan Yitong , Zhang Rongxun , Wang Lin , Zhou Yasong TITLE=Synthesis of Ni-Modified ZSM-5 Zeolites and Their Catalytic Performance in n-Octane Hydroconversion JOURNAL=Frontiers in Chemistry VOLUME=8 YEAR=2020 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2020.586445 DOI=10.3389/fchem.2020.586445 ISSN=2296-2646 ABSTRACT=

Ni-modified ZSM-5 zeolites with different nickel contents were successfully prepared by the in situ synthesis method and the impregnation method. The synthesized samples were characterized by XRD, SEM, N2 adsorption–desorption isothermals, and Py-FTIR. The characterization results show that both the textural properties and crystallization of Ni-modified ZSM-5 zeolites were preserved well, and their acidic properties can be modulated after nickel modification. The corresponding NiMo catalysts supported on Ni-modified ZSM-5 zeolites were prepared by the incipient wetness co-impregnation method, and their catalytic performances were evaluated in n-octane hydroconversion. Compared to the those modified by the in situ synthesis method, ZSM-5 zeolite-supported catalysts modified by the impregnation method exhibit higher stability and higher isomerization selectivity. This is due to the synergistic effect between Brønsted acid sites and Lewis acid sites on the Ni-modified ZSM-5 zeolites, especially for the NiMo/1Ni-Z5 catalyst.