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The metal-support interaction of copper oxide supported on γ-alumina and silica was studied by X-ray diffraction (XRD) and temperature-programmed reduction(TPR). It was found that XRD pattern of CuO can not be observed up to 5.0wt % copper content for CuO/γ-Al2O3 while CuO/SiO2 sample shows the CuO pattern even at 2.5wt% copper content. H2-TPR of CuO/γ-Al2O3 system shows four major peaks at 145℃, 185℃, 210℃, and 250℃. In the case of CuO/SiO2, a large peak at 250℃ was appeared accompanying a small peak at 425℃. Comparing the TPR peaks with that of copper aluminate which was prepared from the calcination of CuO/γ-Al2O3 at 1000℃, the peaks at around 145℃, 200℃ (185℃ and 210℃), and 250℃ were corresponded to Cu+ ion in CuO interacting γ-Al2O3, Cu+ ions in defect sites of γ-Al2O3 and Cu2+ ion in the bulk CuO layer, respectively. From the results, it was concluded that there is considerable metal-support interaction in CuO on γ-Al2O3 and the interaction results in a stabilization of Cu+ ion in the system.
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