CO Oxidation over Nanostructured Ceria Supported Bimetallic Cu–Mn Oxides Catalysts: Effect of Cu/Mn Ratio and Calcination Temperature

• Published in: Catalysis letters 2018, Vol.148 (1), p.181-193
• Main Authors: Lin, Jin, Guo, Yafei, Chen, Xiao, Li, Changhai, Lu, Shouxiang, Liew, Kim Meow
• Format: Article
• Language: English
• Subjects: Adsorption; Catalysis; Catalysts; Cerium; Chemistry; Chemistry and Materials Science; Copper oxides; Industrial Chemistry/Chemical Engineering; Organometallic Chemistry; Oxidation-reduction reactions; Physical Chemistry
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-017-2227-x

Nanostructured CeO 2 supported CuO–MnO 2 (CuMn/Ce) catalysts were synthesized by wet co-impregnation method and compared with CuO/CeO 2 and MnO 2 /CeO 2 catalysts on CO oxidation. The former shows significantly higher catalytic activity toward CO oxidation than the bimetallic oxides catalysts with minimum T 50 . Dual synergistic effects in the interfaces of CuO–MnO 2 and CuO–CeO 2 shall be responsible for the higher oxidation performance of CuMn/Ce catalyst. As Cu/Mn mass ratio varies from 1/0.2 to 1/9, CO oxidation activities of the catalysts present unimodal distribution, and the catalyst with Cu/Mn = 1/1 shows the highest performance (T 50  = 45.8 °C; Ea = 24.11 kJ mol −1 ). Cu acts as CO dissociative adsorption sites, and Mn–Ce supplies activated O species from gas molecule and lattice oxygen, which are both indispensable for improving utilization efficiency of the reactants in the dual redox processes. The catalytic performance of catalyst is also vitally correlated with calcination temperature (160–320 °C). The optimum calcination temperature of CuMn/Ce catalyst is 320 °C. Catalyst characterization results indicate that the pretreatment at 320 °C is decent to obtain desired metal oxides along with fine texture properties. Graphical Abstract