Study of Nickel Catalysts Supported on MnOx–CeO2 Mixed Oxides in Dry Reforming of Methane

Nickel-containing (10 wt % Ni) catalysts supported on CeO2–MnOх oxides with different Ce/Mn ratios (0.25, 1, and 9) have been synthesized and studied in dry reforming of methane (DRM). The low-temperature N2 sorption, XRD, and H2-TPR methods have been used to study the effect of the Ce/Mn ratio on the phase composition of the catalysts and the size and distribution of the Ni-containing oxide precursor to determine the role of MnOx phases and the Ce1 − xMnxO2 − δ solid solution in the formation of the active surface of the catalysts. The addition of manganese oxide contributes to the incorporation of Nin+ cations into the surface structure to form solid solutions, which leads to a decrease in the size of NiO crystallites on the support surface. The synthesized catalysts have been studied in the DRM process in the long-run temperature testing mode for 24 h. The catalyst based on a support with a Ce/Mn weight ratio of 0.25 has exhibited the highest activity and stability in DRM (X(CH4)/X(CO2) = 47/70); this fact has been attributed to the existence of a developed MnOx interface and the presence of fine Ni and MnNiOx particles on the surface.