Hydrogen production by reforming of diesel fuel over catalysts derived from LaCo1−xRuxO3 perovskites: Effect of the partial substitution of Co by Ru (x = 0.01-0.1)

LaCo_1−xRu_xO₃ perovskites with different substitutions of Co by Ru (x = 0.01-0.1) have been investigated as precursors of catalysts for the oxidative reforming of diesel for hydrogen production. The physicochemical characterization of LaCo_1−xRu_xO₃ perovskites revealed modifications in their structure, crystalline size and surface area with the incorporation of ruthenium into the perovskite lattice. The modifications in the perovskites affect the structure and morphology of the catalysts obtained by reduction of perovskites prior the reaction. In the catalysts derived from ruthenium-containing perovskites it is observed a better reducibility, smaller particle size of La₂O₃ and Co⁰ phases and better surface concentration of Ru⁰ particles with the increase in the degree of Co substitution in the perovskite. The modifications in the characteristics of the catalysts induced by the Co substitution in perovskite directly affect their catalytic behaviour in the oxidative reforming of diesel. It is found that the greater Co⁰ + Ru⁰ exposition and the higher extension of the La₂O₂CO₃ phase achieved in catalysts derived from perovskites with higher cobalt degree of substitution produces an increase in the activity and stability of the catalysts derived.