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In this paper, the catalytic properties of La-Ni-M (M = Co, Cu) based materials in dry reforming of methane (DRM) for syngas (CO + H2) production, were studied in the temperature range 773−1073 K. The LaNi0.9M0.1O3 and La2Ni0.9M0.1O4 (M = Co, Cu and Ni/M = 0.9/0.1) catalysts were prepared by partial substitution of Ni by Co or Cu using sol-gel method then characterized by XRD, H2-TPR and N2 physisorption. The XRD analysis of fresh catalysts showed, in the case of Co-substitution, the formation of La-Ni and La-Co perovskite and spinel structures, while only LaNiO3 and La2NiO4 phases were observed for the Cu-substituted samples. The substitution of these two structures by copper decreases the reduction temperature compared to cobalt. The reactivity results showed that the partial substitution of nickel by copper decreases the methane activation temperature, whereas a better stability of catalytic activity and syngas production was obtained via the cobalt-substituted catalysts, which is due to a synergistic effect between Ni and Co. The TPO analysis carried out on the spent catalysts indicated that the lowest carbon deposition was obtained for the cobalt substituted samples. Copyright © 2020 BCREC Group. All rights reserved

NieMgeAlebased catalysts were synthesized by coprecipitation, solegel, and impregnation methods, calcined at 700 C for 4 h and tested in partial oxidation of methane in a temperature range of 500e800 C. The fresh and used unsupported and supported samples were characterized by X-ray diffraction, nitrogen physisorption with Brunauer-Emett-Teller (BET) analysis, and H 2 etemperature-programmed reduction. X-ray diffraction analysis showed, for all samples, the formation of spinel phases MgAl 2 O 4 and/or NiAl 2 O 4 with crystallite sizes of 6e14 nm. H 2 etemperature-programmed reduction analysis showed reduction of two Ni 2þ species (in octahedral and tetrahedral sites of a spinel structure) into metallic nickel known to be responsible for the methane activation. The 10 wt % Ni/MgAl 2 O 4 impregnated catalysts exhibited the highest activity and stability in the partial oxidation of methane reaction, which led mainly to syngas (CO þ H 2 ) at 800 C with a methane conversion close to the thermodynamic equilibrium (95%). A kinetic model revealed that the oxidation of methane occurs on a thin layer of the catalytic bed in which oxygen is consumed and is followed by the production of CO and H 2 by methane steam reforming and water gas shift reactions.