Promoting effect of potassium on sulfur resistance in benzene hydrogenation over Ni₂Mo₃N

To improve sulfur resistance of bimetallic nitrides in benzene hydrogenation reaction, K-promoted (K-Ni₂Mo₃N) catalysts were prepared to investigate the effect of potassium on sulfur resistance. K-Ni₂Mo₃N expressed a higher sulfur resistance than Ni₂Mo₃N when used in benzene hydrogenation with 0.01% thiophene condition. Combined XPS and H₂-TPR characterization results, it could be concluded the potassium species might donate electrons to nickel species to make nickel species an electron-enriched state, which might weaken the interaction bewteen thiophene and nickel species. The TPD-MS results also confirmed the potassium species weakened the thiophene adsorption on the catalyst surface. The critical parameter of sulfur resistance are the suitable adsorption strength which could be handled by the electron condition of active site.