Sr-doped calcium and barium manganites as catalysts in heterogeneous oxidation of volatile organic compounds

Abstract

Sr-doped CaMnO3 and BaMnO3 were prepared by autocombustion (CNA) and coprecipitation and investigated as catalysts for catalytic oxidation of benzene, toluene, ethylbenzene and o-xylene mixture in a fixed-bed reactor. Ethylbenzene and o-xylene were completely removed by all prepared catalysts. Toluene was completely removed by BaMnO3 and Ba0.5Sr0.5MnO3 catalysts prepared by CNA synthesis, while conversions of ∼98% or higher were obtained for all the other prepared catalysts. The highest benzene conversion of 86.43% at 723 K was obtained for the Ba0.7Sr0.3MnO3 catalyst prepared by CNA synthesis. The differences in catalytic activities can be ascribed to Sr-doping, oxygen nonstoichiometry and morphological differences.

Keywords

• Autocombustion synthesis
• Barium manganites
• Calcium manganites
• Catalytic oxidation
• Coprecipitation
• Volatile organic compounds