A Comparative Study of Supported and Bulk Cu–Mn–Ce Composite Oxide Catalysts for Low-Temperature CO Oxidation

• Published in: Catalysis letters 2018-08, Vol.148 (8), p.2348-2358
• Main Authors: Lin, Jin, Guo, Yafei, Li, Changhai, Lu, Shouxiang, Chen, Xiao, Liew, Kim Meow
• Format: Article
• Language: English
• Subjects: Ammonium bromides; Bromine compounds; Catalysis; Catalysts; Cerium; Cerium oxides; Chemical synthesis; Chemistry; Chemistry and Materials Science; Comparative studies; Conversion coating; Copper; Coprecipitation; Industrial Chemistry/Chemical Engineering; Low temperature; Manganese; Organometallic Chemistry; Oxidation; Oxidation-reduction reactions; Physical Chemistry; Precipitation (Meteorology); Sol-gel processes; Solid solutions
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-018-2445-x

A series of supported and bulk Cu–Mn–Ce ternary oxide catalysts was synthesized by wet-impregnation (IM), deposition–precipitation (DP), traditional co-precipitation (CP), co-precipitation with cetyltrimethyl ammonium bromide (CC), and sol–gel (SG) methods. The supported catalysts (CuMn/Ce-IM, CuMn/Ce-DP) exhibited significantly higher activity for CO oxidation than the bulk catalysts (CuMnCe-CP, CuMnCe-CC and CuMnCe-SG). The improved performance could be attributed to the presence of more isolated CuO and MnO x entities on the surface of supported catalysts, which contributed to the efficient utilization of both lattice oxygen from CeO 2 and spillover oxygen from surface MnO x . For bulk catalysts, major Cu–Mn species were doped to form C u x M n y C e 1 - x - y O 2 - z solid solutions and a part of them were coated by ceria mechanically. Lowest 50% CO conversion temperature were achieved at 76.9 °C for CuMn/Ce-IM catalyst. Low-temperature CO oxidation activities of all catalysts were in the sequence of CuMn/Ce-IM > CuMn/Ce-DP > CuMnCe-SG > CuMnCe-CC > CuMnCe-CP. Graphical Abstract