Preparation and Properties of Cubic ZrO2 Stabilized with Ni(II)

摘要

The Fischer-Tropsch activity of the nickel-zirconia system has been investigated and preparations of the catalyst involving coprecipitation gave a significantly more active catalyst than did preparations involving impregnation. Stabilization towards reduction has been observed when certain transition metal ions such as Rh(III) are inserted into the fluorite ZrO2 structure. Recent investigations using the NiO/ZrO2 system have concluded that NiO does not interact with zirconium oxide, but the materials were prepared by incipient wetness. It was the purpose of this study to investigate the formation of cubic ZrO2 stabilized with Ni(II) and to relate the structural properties of the catalyst with its observed stability in reducing atmospheres. These properties were then compared to those of catalysts prepared by incipient wetness. Changes in the structure of ZrO and in the temperatures at which reduction of Ni(II) to Ni metal occurred were then related to the relative strengths of the catalyst-support interaction.