Influence of ferric oxide modification on the properties of copper oxide supported on γ-alumina

Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
Journal of Colloid and Interface Science (Impact Factor: 3.37). 03/2010; 343(2):522-528. DOI: 10.1016/j.jcis.2009.11.050


X-ray diffraction (XRD), Mössbauer spectroscopy, and temperature-programmed reduction (TPR) were employed to investigate the dispersion and reduction behaviors of the Fe2O3/CuO/γ-Al2O3 system. The results indicated that: (1) the crystalline CuO particle in the CuO/γ-Al2O3 samples was redispersed during impregnating CuO/γ-Al2O3 samples with Fe(NO3)3 solutions; (2) two different dispersion states of surface iron species could be observed, i.e., State I corresponding to the iron(III) species located in the D layer on the surface of γ-Al2O3 and State II corresponding to those in the C layer. The dispersed states of surface iron(III) species were closely related to the iron loading amount; (3) the copper species located in the D layer of alumina surface was easily reduced and the copper species located in the C layer were more stable, which could be due to the influence of the iron(III) species in the different layers; (4) in the NO+CO reaction, the catalytic performances were enhanced due to the Cu–Fe synergism and the main active species in this system should be the surface-dispersed copper oxide species.

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Available from: Bin Liu, Mar 09, 2015
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