TEMPERATURE-PROGRAMMED REDUCTION OF ALUMINA-SUPPORTED NI-PT SYSTEMS

A series of alumina-supported nickel-platinum systems containing varying amounts of both components has been studied by temperature-programmed reduction (TPR) and oxidation (TPO), X-ray diffraction ()(RD) and hydrogen chemisorption. The reduction of calcined catalyst precursors was enhanced by even a small amount of platinum dopant. Alloy formation was established by both TPR and XRD methods, although the linear relationship between the lattice parameters and the bimetallic composition (Vegard's law) was not followed. Chemisorption data indicate an enrichment of the surface of the catalysts in nickel.