Enhancing the dry reforming of methane over Ni-Co-Y/WC-AC catalyst: Influence of the different Ni/Co ratio on the catalytic performance

[Display omitted] •Catalysts with different Ni/Co ratio were synthesized for DMR.•The 10Ni-8Co-10Y/WC-AC catalyst shows the best activity and stability.•The addition of Co improves the adsorption and anti-coking ability of the catalyst.•The synergistic effect between Ni and Co enhances the catalyst performance. In this paper, a series of bimetallic catalysts with different Ni/Co ratios were prepared by co-impregnation method for application in methane dry reforming reaction. The effects of different Ni/Co ratios on the catalyst performance were investigated. The catalysts were characterized by XRD, BET, H2-TPR, TG, TEM and FTIR. The results showed that after the introduction of a certain amount of Co, the synergistic effect between Ni and Co enhanced the active component-carrier interaction, thus improving the dispersion of the active component of the catalyst, reducing the particle size of the metal, and increasing the activity of the catalyst. Meanwhile, the mechanistic study showed that the introduction of Co species with strong oxygen affinity facilitated the formation of oxygen vacancies. It makes the catalysts contain higher lattice oxygen and carbonate species, which was conducive to the elimination of carbon accumulation, thus improving the stability of catalysts. Therefore, the 10Ni-8Co-10Y/WC-AC catalyst exhibited excellent dry reforming of methane (DRM) performance at a Ni/Co ratio of 5:4. The conversions of CO2 and CH4 were 95 % and 88 % at 800 °C under atmospheric pressure, respectively.