The bulk and supported perovskite-type catalysts for the CO2 reforming of methane: The effect of ceria and magnesia

• The alumina and magnesia-modified alumina increased the dispersion of nickel by formation of various species (nickel-aluminate and nickel-magnesia solid-solution). • These species are beneficial that dispersed the nickel metal, suppressed the nickel sintering, increased the number of active sites, decreased the lattice oxygen (O 2− ) and increased the surface adsorbed oxygen (-OH) assisted for the DRM reaction. • The modified supported catalyst (50La 0.5 Ce 0.5 NiO 3 /8MgO-Al 2 O 3 ) is more active than the bulk catalyst with higher percent conversion, and a very low coke deposition during the dry reforming of methane. The bulk or supported nickel catalysts are active in the dry reforming of methane to produce syngas. The nickel-based catalysts are deactivated quickly due to the metal sintering and coke deposition. Perovskite catalysts are stable, enhance the dispersion of the active sites, and resist metal sintering and coke deposition. The coke deposition is inhibited by increasing the CO 2 adsorption and oxidation of the deposited coke. A series of ceria-doped perovskite catalysts La 1-x Ce x NiO 3 , LaNi 1-x Ce x O 3 and magnesia-modified-alumina supported perovskite-type catalysts were prepared via the sol-gel method. The prepared catalysts were thoroughly characterized via state-of-the-art characterization techniques. The incorporation of ceria assisted the supported catalysts in forming a dispersed phase at low loading and forming other NiO or NiO-MgO (solid solution) NiAl 2 O 4 and MgAl 2 O 4 (spinel phase). The catalytic activity for the CO 2 reforming of methane reaction increased with the addition of magnesia and the substitution of La-ion with tetravalent metal cation (ceria). The doping of ceria increased the stability of the catalyst. The bulk catalyst La 0.5 Ce 0.5 NiO 3 exhibited promising catalytic activity. The magnesia-modified-alumina-supported catalyst (50La 0.5 Ce 0.5 NiO 3 /8MgO-Al 2 O 3 ) was more active than the alumina-supported or bulk-perovskite catalysts with low coke deposition and higher percent conversion of CH 4 (97%) and CO 2 (99%) at 1073 K.