Catalytic performance of NixCoy catalysts supported on honeycomb-lantern-like CeO2 for dry reforming of methane: Synergistic effect and kinetic study

Dry reforming of methane (DRM) is considered one of the most efficient methods for carbon utilization, as it can transform greenhouse gases (CH 4 and CO 2 ) into syngas (CO and H 2 ) which could be widely used in the production of high-value hydrocarbons. The synergistic effect between Ni and Co is leveraged to enhance the coke resistance and stability of Ni-based catalyst during the DRM process, building upon the surface spatial confinement provided by honeycomb-lantern-like CeO 2 support. The enhanced catalytic performance of Ni 0.9 Co 0.1 catalyst can be attributed primarily to the addition of cobalt, which facilitates CO 2 adsorption and activation, further promotes the Boudouard reaction and aids in the elimination of coke. This phenomenon is supported by evidence from CO 2 -TPD, XPS, SEM, TGA, XRD, and CO 2 -TPO analyses. Furthermore, the kinetics of Ni 0.9 Co 0.1 are examined using Power-Law (PL) and Langmuir-Hinshelwood (LH) mechanisms, obtaining the explicit equations for the rate constants ( k and k r ), reaction orders of the reactants (α and β), and adsorption equilibrium constants ( K CH 4 ${\mathit{K}}_{{\text{CH}}_4}$ and K CO 2 ${\mathit{K}}_{{\text{CO}}_2}$ ). The comparison of the predicted CH 4 consumption rates with the experimental rates suggests that the LH mechanism is notably more precise than PL mechanism for Ni 0.9 Co 0.1 catalyst. Moreover, the relevant kinetic parameters (the activation energy and pre-exponential factor), pertinent to coke gasification process for the spent Ni 0.9 Co 0.1 and Ni 1.0 , are determined and calculated through CO 2 -TPO characterization and the modified Wigner-Polanyi equation.