Stable and selective perovskite catalyst for dehydrogenation of propane working with redox mechanism

• LaCo0.2Mn0.8O3 catalyst was active and selective for DHP with steam among various catalysts.
• LaCo0.2Mn0.8O3 catalyst showed high stability even in a reducing atmosphere.
• The catalyst showed higher propylene selectivity than CrOx/γ-Al2O3 at the same conversion.
• The catalyst worked by redox mechanism using lattice oxygen and steam.
• Supplied steam suppressed coke formation and promoted redox of lattice oxygen.

Dehydrogenation of propane with steam was investigated using novel LaCoxMn1−xO3 (0 ≤ x ≤ 1) perovskite-type oxide (ABO3) catalysts. Optimization of the Co substitution ratio (x = 0.2) enabled high propylene yield and selectivity. The perovskite structure of LaCo0.2Mn0.8O3 remained stable during dehydrogenation, as confirmed by XRD measurements. Dehydrogenation of propane over LaCo0.2Mn0.8O3 perovskite catalyst proceeded via reduction–oxidation (redox) of the perovskite oxide; oxidative dehydrogenation of propane consumed lattice oxygen in the perovskite and the consumed lattice oxygen was regenerated by H2O. Surface analyses conducted using XPS and XANES showed that a part of Mn4+ and Co3+ in LaCo0.2Mn0.8O3 was reduced to Mn3+ and Co2+ during the reaction. The LaCo0.2Mn0.8O3 catalyst showed higher selectivity at the same propane conversion compared with the selectivity to propylene over an industrial CrOx/γ-Al2O3 catalyst.

Figure optionsDownload high-quality image (119 K)Download as PowerPoint slide