Effect of preparation method on the activity of bimetallic Ni-Co/Al2O3 catalysts for dry reforming of methane

Ni-Co/γ-Al2O3 bimetallic catalysts were synthesized by capillary impregnation (CI) and solution combustion methods (SC). Catalysts tested in dry methane reforming (DRM), characterized by XRD, H2-TPR, SEM, small-angle X-ray scattering. Preparation method plays an important role in regulating the textural and morphological properties of catalysts and provides a difference in indices of their activity. Synthesis of Ni-Co/γ-Al2O3 by SC in comparison with CI method leads to formation of solid solution of NiCo2O4 with a CSR size of 21 nm, increases the proportion of metal ions (Ni, Co) reduced at temperatures of 400–700 °C, uniform distribution of nanosized particles of active phase on carrier surface. At comparatively low reaction temperature (600 °C) on sample synthesized by SC, degree of methane conversion is higher compared to sample prepared by CI, XCH4-69%, XCH4-65%, respectively. SC provides an efficient way to develop an active catalyst for DRM at low temperatures (600–750 °C).