Determination of U3O8 in UO2 by infrared spectroscopy

Abstract

The oxygen-uranium (O-U) system has various oxides, such as UO 2 , U 4 O 9 , U 3 O 8 , and UO 3 . Uranium dioxide is the most important one because it is used as nuclear fuel in nuclear power plants. UO 2 can have a wide stoichiometric variation due to excess or deficiency of oxygen in its crystal lattice, which can cause significant modifications of its proprieties. O/U relation determination by gravimetry cannot differentiate a stoichiometric deviation from contents of other uranium oxides in UO 2 . The presence of other oxides in the manufacturing of UO 2 powder or sintered pellets is a critical factor. Fourier Transform Infrared Spectroscopy (FTIR) was used to identify U 3 O 8 in samples of UO 2 powder. UO 2 can be identified by bands at 340 cm -1 and 470 cm -1 , and U 3 O 8 and UO 3 by bands at 735 cm -1 , 910 cm -1 , respectively. The methodology for sample preparation for FTIR spectra acquisition is presented, as well as the calibration for quantitative measurement of U 3 O 8 in UO 2 . The content of U 3 O 8 in partially calcined samples of UO 2 powder was measured by FTIR with good agreement with X-rays diffractometry (XRD).

Characterization of the Siderurgy Slags as the Presence of Natural Radionuclides

“…In the other study FTIR was used to identify U3O8 in samples of UO2 powder. UO2 can be identified by bands at 340 cm −1 and 470 cm −1 , and U3O8 and UO3 by bands at 735 cm −1 and 910 cm −1 , respectively [8]. In this work we observed in Figure 2a FTIR absorption bands between 300 cm −1 and 2000 cm −1 that are attributed to minerals signalized by the XRD technique, such as calcite, portlandite and larnite.…”

Optical and Chemical Characterization of Uranium Dioxide (UO2) and Uraninite Mineral: Calculation of the Fundamental Optical Constants

“…Furthermore, we find the spectral width of the reststrahlen band agrees well with earlier models and measurements; here our experimentally calculated reststrahlen bandwidth is ω r = 294 cm −1 . Related to Table 1, we note that uraninite is known to readily oxidize 42,43 and incorporate atmospheric oxygen into its crystal lattice resulting in higher oxides such as UO 3 , U 4 O 9 , and U 3 O 8 . It has also been known 44 for some time that interstitial oxygens in UO 2 affect the measured infrared spectra.…”

“…Related to Table , we note that uraninite is known to readily oxidize , and incorporate atmospheric oxygen into its crystal lattice resulting in higher oxides such as UO 3 , U 4 O 9 , and U 3 O 8 . It has also been known for some time that interstitial oxygens in UO 2 affect the measured infrared spectra.…”

Recent Advances in Nuclear Forensic Chemistry

“…50 Different compositions of uranium oxide, such as UO 2 and U 3 O 8 , can be readily distinguished by IR spectroscopy, providing information about the processing history of the material (Figure 3). 51 IR spectroscopy is also used within nuclear forensics to characterize collateral evidence accompanying seized nuclear materials. In a well-known example, a vial of highly enriched uranium (HEU) contained in a wax-filled lead pig was seized in Bulgaria, and the wax was subjected to IR spectroscopy, in conjunction with other methods, to determine where the sample had originated.…”

“…Eng. J. , 2017 , 70 , 59–62 (ref ) under a Creative Commons Attribution 4.0 International License (). (Bottom) SEM image and (b) space-wavelength Raman spectrum of a uranium oxide thin film.…”