Enhanced Performance of the OMS-2-Supported CuOx Catalysts for Carbon Monoxide, Ethyl Acetate, and Toluene Oxidation

Catalysts

Hongxing Dai¹  Mengyue Chen²  Ning Dong²  Qing Ye²  Zhidan Fu² 

[1] Beijing Key Laboratory for Green Catalysis and Separation, Key Laboratory of Beijing on Regional Air Pollution Control, and Laboratory of Catalysis Chemistry and Nanoscience, Department of Environmental Chemical Engineering, School of Environmental and Chemical Engineering, Faculty of Environment and Life Science, Beijing University of Technology, Beijing 100124, China;Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, School of Environmental and Chemical Engineering, Faculty of Environment and Life Science, Beijing University of Technology, Beijing 100124, China;

关键词: cryptomelane-type manganese oxide;    OMS-2;    supported CuO_x catalysts;    carbon monoxide oxidation;    volatile organic compounds oxidation;   

DOI  :  10.3390/catal11060713

来源: DOAJ

【 摘 要 】

Different Cu contents (x wt%) were supported on the cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2) (xCu/OMS-2; x = 1, 5, 15, and 20) via a pre-incorporation method. Physicochemical properties of the OMS-2 and xCu/OMS-2 samples were characterized by means of the XRD, FT-IR, SEM, TG/DTG, ICP-OES, XPS, O₂-TPD, H₂-TPR, and in situ DRIFTS techniques, and their catalytic activities were measured for the oxidation of CO, ethyl acetate, and toluene. The results show that the Cu species were homogeneously dispersed in the tunnel and framework structure of OMS-2. Among all of the samples, 15Cu/OMS-2 sample exhibited the best activities with the T_50% of 65, 165, and 240 °C as well as the T_90% of 85, 215, and 290 °C for CO, ethyl acetate and toluene oxidation, respectively, which was due to the existence of the Cu species and Mn³⁺/Mn⁴⁺ redox couples, rich oxygen vacancies, good oxygen mobility, low-temperature reducibility, and strong interaction between the Cu species and the OMS-2 support. The reaction mechanisms were also deduced by analyzing the in situ DRIFTS spectra of the 15Cu/OMS-2 sample. The excellent oxygen mobility associated with the electron transfer between Cu species and Mn³⁺/Mn⁴⁺ redox couples might be conducive to the continuous replenishment of active oxygen species and the constantly generated reactant intermediates, thereby increasing the reactant reaction rate.

【 授权许可】

Unknown