The LaCo1−xVxO3 Catalyst for CO Oxidation in Rich H2 Stream

Abstract

The LaCo1−xVxO3 catalysts for CO oxidation in H2 rich stream were studied. These perovskite-type oxides with variable amounts of vanadium (x = 0, 0.05 and 0.1) were synthesized by modified citrate method. It was found that the modification in LaCoO3 perovskite after vanadium addition affected directly the structure and morphology leading to decrease in the crystallite size and increase in BET surface area. XPS results confirmed quantitatively the higher presence of V4+ species at the surface of the modified perovskite. The existence of Co2+ was reported to facilitate the interplay between Co2+/Co3+ and V5+/V4+ redox couples, which can enhance the lattice oxygen mobility and create interfacial active sites of CoOx/V2O5. Tests during 20 h on stream at 250 °C showed excellent stability, high resistance to coke deposition and no sintering. Perovskite modified by addition of vanadium LaCo1−xVxO3 for preferential CO oxidation in H2-rich stream.