Catalysis Communications | 2019
The effect of hydrogen on thiophene catalytic removal over Ni/Al2O3
Abstract
Abstract To investigate the essential role of H2 on thiophene removal over supported nickel catalysts, a NiO/Al2O3 catalyst was prepared, and a series of desulfurization reactions were carried out with different H2 feed concentrations. The characterization of fresh and spent catalysts indicated that reduced nickel (Ni0), which showed dependence on the H2 feed concentration, was the key factor to the thiophene reactive adsorption desulfurization (RADS) process. The equilibrium between sulfurization and reduction of nickel species retained the activity of the catalyst. The stability of the formed nickel sulfides was related to the H2 feed concentration. The higher H2 feed concentration favored the RADS process for the positive auto-regeneration of the nickel species.