Author(s)

Gina Pecchi^1*, Ruddy Morales¹, Daniela Salinas¹, Eduardo J. Delgado¹, José Luis García Fierro²

¹Facultad Ciencias Químicas, Universidad de Concepción, Concepción, Chile.
²Instituo Catálisisy Petroleoquímica, CSIC, Cantoblanco, Madrid, Spain.

Substituted La_0.6Ca_0.4Fe_1-xNi_xO₃ (0.0 ≤ x ≤ 1.0) perovskite-type oxides prepared by the amorphous citrate method have been investigated as catalysts in the dimethyl ether (DME) oxidation reaction. The samples with an x ≤ 0.3 composition show an orthorhombic structure, while the intermediate compositions with 0.5 ≤ x ≤ 0.9 show a less crystalline orthorhombic perovskite structure with segregated phases that increase upon increasing the Ni content. The progressive substitution of Fe³⁺ by Ni²⁺ in La_0.6Ca_0.4FeO₃ entails the progressive formation of oxygen vacancies and Fe⁴⁺ species for Ni substitution degrees of x ≤ 0.5. For larger degrees of substitution with x > 0.7, segregated phases and a progressive loss of the perovskite structure are detected. The highest catalytic performance for the total combustion of DME is obtained from equimolar substitution in the B-site position (Fe_0.5Ni_0.5), in which a large extent of Fe⁴⁺ species and oxygen vacancies are present.

DME, Perovskites, Oxidation, Iron, Nickel

Pecchi, G. , Morales, R. , Salinas, D. , Delgado, E. and Fierro, J. (2015) Catalytic Performance of La_0.6Ca_0.4Fe_1-xNi_xO₃ Perovskites in DME Oxidation. Modern Research in Catalysis, 4, 97-106. doi: 10.4236/mrc.2015.44012.