Properties of lanthanide oxides as supports for transition metal catalysts. Final technical report.

摘要

The overall objective of this research program has been to develop an improved understanding of not only the catalytic and surface properties of the pure lanthanide oxides, but of the behaviors that they induce when used as oxidic supports for dispersed transition metal catalysts. Suitable experimental methods were developed to enable preparation of several of the lanthanide oxides having substantially higher surface areas than those of commercially available materials. In order to fully characterize the surface and bulk properties of the prepared oxides, we have employed a wide variety of physical and instrumental techniques, including thermal gravimetric analysis, differential thermal analysis, temperature-programmed dehydration/decomposition selective chemisorption, x-ray diffraction, infrared spectroscopy, scanning and transmission electron microscopy, and x-ray photoelectron spectroscopy. Catalytic behaviors of the pure oxides were probed using several diagnostic-type reactions, such as isomerization/hydrogenation of alkenes and dehydration/dehydrogenation of alcohols, while the catalytic properties of transition metals supported on the oxides were investigated for CO hydrogenation and for the hydrogenolysis and dehydrocyclization of alkanes.