Catalysis Today, Vol.133, 142-148, 2008
Dry reforming of CH4 over solid solutions of LaN1-xCoxO3
LaN1-xCoxO3 perovskite-type oxides were synthesized by the sol-gel resin method and used as catalysts precursors in the dry reforming of methane to syngas between 600 and 800 degrees C at atmospheric pressure, the reaction was studied under continuous flow using an mixture of CH4:CO2 = 1:1. The solids were characterized by X-ray diffraction (XRD), BET specific surface area and temperature-programmed reduction (TPR). XRD analysis of the solids shows LaNiO3 and/or LaCoO3 as the main phases present on the solids depending on the degree of substitution. The more intense peaks and cell parameters showed formation of Ni-Co solid solutions. The as-synthesized solids were reduce during catalytic tests to form Ni-0, Co-0 and La2O2CO3 as the active phases which remain during the reaction and are responsible for the high activity shown by the solids inhibiting carbon formation, with CH4 and CO2 equilibrium conversions near 100%, except for LaCoO3 that showed a poor activity. (c) 2008 Elsevier B.V. All rights reserved.
Keywords:resin method;(Ni;Co)-solid solutions;(Ni;Co)-perovskites;dry reforming of methane;syngas production;catalytic activity;carbon deposition