Effect of sulfidation pressure on the structure and activity of Ni(CyDTA)W/γ-Al2O3 hydrodesulfurization catalysts

In this paper NiW/γ-Al2O3catalysts were prepared by consecutive impregnation of a W/γ-Al2O3 catalyst with an aqueous solution nickel salt. The structural control the ion precursor in was achieved addition 1, 2-cyclohexanediamine-N, N, N’, N’-tetraacetic acid (CyDTA) as chelating agent at different pH. influence sulfidation pressure (1 bar vs 40 bar) on activity and structure NiW catalysts investigated. performances tested hydrodesulfurization (HDS) thiophene after atmospheric or high pressure. characterized X-Ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) infrared adsorbed CO (IR/CO) to explain modification surface species composition due CyDTA sulfiding conditions. presence CydTA sulfided under displayed highest HDS activity. These two factors enhanced degree W-based XPS. A linear correlation found between degree. addition, induced decrease metal-support interaction, pointed out TPR, strongly favored creation CUS sites NiWS phase seen IR/CO. All these features catalytic not only leads more active but improved butene-over-butane ratio.