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

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