TY - JOUR
T1 - Effect of sulfidation pressure on the structure and activity of Ni(CyDTA)W/γ-Al2O3 hydrodesulfurization catalysts
AU - Santolalla-Vargas, C. E.
AU - Santes, Victor
AU - Suarez-Toriello, V. A.
AU - de los Reyes, J. A.
AU - Pawelec, B.
AU - Fierro, J. L.G.
AU - Garcia, E. Dominguez
AU - Oliviero, L.
AU - Maugé, F.
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/10/1
Y1 - 2021/10/1
N2 - In this paper NiW/γ-Al2O3catalysts were prepared by consecutive impregnation of a W/γ-Al2O3 catalyst with an aqueous solution of nickel salt. The structural control of the nickel ion precursor in the impregnation solution was achieved by the addition of 1, 2-cyclohexanediamine-N, N, N’, N’-tetraacetic acid (CyDTA) as a chelating agent at different pH. The influence of the sulfidation pressure (1 bar vs 40 bar) on the activity and structure of the NiW catalysts was investigated. The catalysts performances were tested in hydrodesulfurization (HDS) of thiophene after sulfidation at atmospheric or high pressure. The catalysts were characterized by X-Ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) and infrared spectroscopy of adsorbed CO (IR/CO) to explain the modification in surface species composition due to the chelating agent CyDTA and sulfiding conditions. NiW catalysts prepared in presence of CydTA and sulfided under high pressure displayed the highest HDS activity. These two factors enhanced the sulfidation degree of W-based species as characterized by XPS. A linear correlation was found between the HDS activity and the sulfidation degree. In addition, chelating agent addition induced a decrease on metal-support interaction, as pointed out by TPR, and strongly favored the creation of CUS sites on the NiWS phase as seen by IR/CO. All these features favored a high catalytic activity. In addition, high pressure sulfidation not only leads to more active NiW catalysts but improved the butene-over-butane ratio.
AB - In this paper NiW/γ-Al2O3catalysts were prepared by consecutive impregnation of a W/γ-Al2O3 catalyst with an aqueous solution of nickel salt. The structural control of the nickel ion precursor in the impregnation solution was achieved by the addition of 1, 2-cyclohexanediamine-N, N, N’, N’-tetraacetic acid (CyDTA) as a chelating agent at different pH. The influence of the sulfidation pressure (1 bar vs 40 bar) on the activity and structure of the NiW catalysts was investigated. The catalysts performances were tested in hydrodesulfurization (HDS) of thiophene after sulfidation at atmospheric or high pressure. The catalysts were characterized by X-Ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) and infrared spectroscopy of adsorbed CO (IR/CO) to explain the modification in surface species composition due to the chelating agent CyDTA and sulfiding conditions. NiW catalysts prepared in presence of CydTA and sulfided under high pressure displayed the highest HDS activity. These two factors enhanced the sulfidation degree of W-based species as characterized by XPS. A linear correlation was found between the HDS activity and the sulfidation degree. In addition, chelating agent addition induced a decrease on metal-support interaction, as pointed out by TPR, and strongly favored the creation of CUS sites on the NiWS phase as seen by IR/CO. All these features favored a high catalytic activity. In addition, high pressure sulfidation not only leads to more active NiW catalysts but improved the butene-over-butane ratio.
KW - 1, 2-cyclohexanediamine-N, N, N”, N”-tetraacetic acid
KW - Adsorbed CO
KW - Hydrodesulfurization
KW - Nickel
KW - Thiophene
KW - Tungsten
UR - http://www.scopus.com/inward/record.url?scp=85089457622&partnerID=8YFLogxK
U2 - 10.1016/j.cattod.2020.07.015
DO - 10.1016/j.cattod.2020.07.015
M3 - Artículo
AN - SCOPUS:85089457622
SN - 0920-5861
VL - 377
SP - 92
EP - 99
JO - Catalysis Today
JF - Catalysis Today
ER -