Novel supported uranium oxide catalysts for NOx abatement

Abstract

The catalytic reduction of NO has been studied over novel supported uranium oxide catalysts which exhibit comparable activity and selectivity to that of conventional supported Pt catalysts and for which in situ XRD identifies the active phase to be UO x (2 < x < 2.25).

Photoluminescence properties of U in SrBPO5 host: Effect of concentration and annealing temperature

“…Among the actinide elements photo luminescence studies of uranium activated solid matrices have gained much attention owing to its application in the nuclear industries, as the requirement of inert solid matrix for incorporation of nuclear waste is a challenging area of investigation [5]. Uranium activated matrices are well known and promising catalyst for thermal degradation of pollutant molecules [6]. Moreover many uranium doped solid matrices are known to be efficient green light emitting phosphor [7].…”

“…Consequently, the PL properties like excitation, emission and life time data are greatly influenced by the symmetry and coupling to external vibrational modes of closely lying ligands and crystal fields that in turn makes it an useful probe for investigating the co-ordination environment [14]. In solids the crystal structure of host matrix and synthesis conditions are responsible factors for stabilization of Uranium in different forms such as octahedral/tetrahedral uranium groups (UO 6 6− , UO 4 2− and U 6 þ ) other than the usual uranyl species [15]. Thus stabilization of uranium indirectly gives information about the lattice chemistry as well as the crystal field experienced in that particular matrix.…”

Investigation of reactivity and structure formation in a K–Te–U oxo-system under high-temperature/high-pressure conditions

“…These framework materials attract significant interest because they are able to accommodate guest atoms, ions or molecules in their cavities. This feature enables them to demonstrate extraordinary physicochemical performance, including selective-oxidation catalysis, 16,17 ionic exchange properties, 18,19 and storage metrics for radionuclides. 20 In recent years, due to the improvement of chemical technology and the arduous efforts of research, uranium compounds have undergone a respectable rate of expansion with a great quantity of products being isolated and chemically elucidated almost on a weekly basis.…”

The characterisation by luminescence spectroscopy of uranium(VI) incorporated into zeolites and aluminas

“…There is currently considerable interest in the incorporation of the uranyl ion into solid matrices. This stems from the needs of incorporating nuclear wastes in inert solids for long-term storage [1,2], the possibility of using excited uranyl ion as a photocatalyst [3±5] and the potential that uranium oxides have as ef®cient catalysts for the thermal degradation of pollutant molecules [6,7]. However, to understand these systems, it is important to obtain information on the way that uranium is incorporated.…”