Methanation of CO in hydrogen-rich gas on Ni–Ru/SiO2 catalyst: The type of active sites and Ni–Ru synergistic effect

Abstract The Ru-additive or Ru-free Ni-based catalysts were applied in the methanation of CO in hydrogen-rich gas. In situ CO chemisorbed infrared spectroscopy exhibited that the defect sites formed on the metallic Ni 0 particles dominated the reaction activity. As compared with the monometallic Ni–P catalyst, the addition of Ru increased the defect sites. This Ni–Ru synergistic effect depended on the particle structure. The NiRu–P catalyst with bimetallic Ni–Ru particles formed the defect sites ∼3 fold more than NiRu–NP catalyst whose Ru separated from Ni 0 particles. Consequently, the methanation activity decreased in the order of NiRu–P > NiRu–NP > Ni–P catalyst.