Hydrodesulfurization and isomerization performance of model FCC naphtha over sulfided Co(Ni)–Mo/Y catalysts

The process of deep hydrodesulfurization (HDS) in gasoline typically results in the saturation of olefins , leading to significant reductions in octane number. In this work, Y-supported Co(Ni)–Mo catalysts that with different Ni–Co content were prepared by the incipient wetness impregnation method, the structure and properties were characterized and analyzed using HRTEM, XPS, H 2 -TPR, and NH 3 -TPD. The isomerization of 1-hexene and 1-octene as well as the HDS of thiophene were studied by using model FCC naphtha. The incorporation of Ni was found to enhance the number of MoS 2 stacking layers, thereby improving the degree of sulfurization in Mo and subsequently increasing the desulfurization rate, with a maximum achieved desulfurization rate of 94.7%. When employing a Ni/Co ratio of 3:2, optimal synergy between Ni and Co is achieved, resulting in a greater presence of multi-layer stacked II-Co(Ni)MoS active phases. Additionally, appropriate Brønsted acidity levels are maintained to facilitate efficient olefin isomerization while preserving high HDS activity. As a result, the current isomerization yield stands at 58.2%(mass). These understandings shed light on the development of highly HDS and olefin isomerization catalysts.