title: In situ ultraviolet Raman spectroscopy of the reduction of chromia on alumina catalysts.
abstract: A fluidized bed in situ cell is used to examine the chromia on alumina catalyst surface. The loading is varied from 1 to 20% chromium oxide on alumina. The structure of the surface is monitored as a function of temperature, reduction, and hydration. This is the first study to use ultraviolet excitation to study a reduced chromium catalyst surface. Reduction of the sample in hydrogen gas leads to the formation of noncrystalline Cr(3+) species. Addition of potassium to the surface reduces the size of the chromia clusters.
authors.affiliation: Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: Vivian S
authors.initials: VS
authors.lastname: Sullivan
authors.forename: S David
authors.initials: SD
authors.lastname: Jackson
authors.forename: Peter C
authors.initials: PC
authors.lastname: Stair