Catalytic oxidation of toluene over LaBO3 (B= Fe, Mn and Co) and LaCo0.7B′0.3O3 (B′= Fe and Mn) perovskite-type

Abstract

In this paper, LaBO3 perovskite type catalyst formulations were prepared by sol-gel auto combustion method using citric acid as the fuel. Activity of catalysts was tested in catalytic oxidation of toluene as a model of volatile organic compounds. LaCoO3 perovskite formulation showed the highest activity among LaBO3 (Fe, Mn and Co) perovskite catalysts. So, LaCoO3 perovskite based catalyst was selected for further investigation and modification in order to improve catalytic activity. LaBO3 perovskite catalysts were modified by substitution of Co by Fe and Mn. The catalytic activity of LaCoO3 improved due to partial substitution of Co by Fe and Mn cations. LaCo0.7Mn0.3O3 showed the highest catalytic activity among the synthesized catalysts. The structures and morphology of synthesized perovskites were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. The results of X-ray diffraction indicated that the LaBO3 and LaCo0.7B′0.3O3 samples obtained using sol-gel method had a pure perovskite-type crystal structure.