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Two series of Cu/ZSM-5 catalysts,loading from 5 to 20 wt% CuO.were prepared by thedeposition-precipitation and impregnation methods,respectively.The catalysts prepared by the impregnation method showed better catalytic performances than those prepared by the deposition-precipitationmethod and the increase of copper loading favored methane conversion.2OCu(I)/ZSM-5 had the highestactivity with T90% of 746 K,and for 20Cu(D)/ZSM-5,T90% was as high as 804 K.The characterization of X-ray diffraction (XRD),temperature-programmed reduction(TPR),temperature-programmed desorption(TPD),and X-ray photoelectron spectroscopy (XPS) revealed that the dispersion of copper species could be improved by using the deposition-precipitation method instead of the impregnation method,but the fraction of surface CuO,corresponding to active sites for methane oxidation,Was larger on 20Cu(I)/ZSM-5 than 20Cu(D)/ZSM-5.The results of Pyridine-Fourier transform infrared spectrum(Py-FT-IR)showed that a majority of Lewis acidity and a minority of Bronsted acidity were present on Cu/ZSM-5 catalysts.20Cu(I)/ZSM-5 presented more Lewis acid sites.The number of Lewis acid sites changed significantly with preadsorption of oxygen.Adsorption of methane and oxygen on acid sites Was observed.The properties of Cu/ZSM-5 catalysts were correlated with the activity for methane oxidation.