Several SAPO-11-Al2O3 supports with different amounts of SAPO-11 were used to prepare a series of CoMo/ SAPO-11-Al2O3 catalysts by the impregnation method with or without addition of citric acid. Hydrodesulfurization (HDS) of 4,6-dimethyldibenzothiophene, hydrodenitrogenation (HDN) of acridine, and hydrodearomatization (HDA) of o-xylene, 1-methylnaphthalene and phenanthrene were carried out to evaluate the catalytic activity of the catalysts. The catalysts were characterized by BET, XRF, NH3-TPD, XPS and TEM. The acidity of the supports strongly affected the active slabs structure and activity of the catalysts. 20 wt% SAPO-11 added catalyst showed lower HDA, HDS and HDN activities compared to CoMo/Al2O3 catalyst. The length and stacking number of CoMoS active slabs on the former increased because of decreased dispersion of Mo species due to the reduction in number of strong acid sites on the support surface in the presence of SAPO-11. Addition of citric acid during active metal impregnation decreased HDA activity but increased HDS and HDN activities due to improvement of Mo species dispersion, resulting in formation of shorter length and higher stacking of CoMoS active slabs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.