Temperature-Programmed Reduction of Copper Oxide Supported on -Al2O3 and SiO2

摘要

The metal-support interaction of copper oxide supported on ￥?-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/￥?-Al2O3 while CuO/SiO2 sample shows the CuO pattern even at 2.5wt% copper content. H2-TPR of CuO/￥?-Al2O3 system shows four major peaks at 145?é, 185?é, 210?é, and 250?é. In the case of CuO/SiO2, a large peak at 250?é was appeared accompanying a small peak at 425?é. Comparing the TPR peaks with that of copper aluminate which was prepared from the calcination of CuO/￥?-Al2O3 at 1000?é, the peaks at around 145?é, 200?é (185?é and 210?é), and 250?é were corresponded to Cu+ ion in CuO interacting ￥?-Al2O3, Cu+ ions in defect sites of ￥?-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 ￥?-Al2O3 and the interaction results in a stabilization of Cu+ ion in the system.