X-ray absorption spectroscopic studies at the cobalt K-edge on a reduced Al_2O_3-supported rhenium-promoted cobalt fischer-tropsch catalyst

摘要

In situ XAFS spectroscopic studies have been carried out at 450 deg C on the hydrogen reduction of rhenium-promoted Co_3O_4/Al_2O_3 catalyst. The results show that reduction at this temperature yields a highly dispersed system with small cobalt metal particles (＜40 ?). In addition, a lower fraction of the cobalt content is randomly dispersed over the tetrahedral vacancies of the alumina support. This dispersion occurs during reduction and not calcinations.