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Title: Identification of Uranyl Minerals Using Oxygen K-Edge X Ray Absorption Spectroscopy

Abstract

Uranium analysis is consistently needed throughout the fuel cycle, from mining to fuel fabrication to environmental monitoring. Although most of the world’s uranium is immobilized as pitchblende or uraninite, there exists a plethora of secondary uranium minerals, nearly all of which contain the uranyl cation. Analysis of uranyl compounds can provide clues as to a sample’s facility of origin and chemical history. X-ray absorption spectroscopy is one technique that could enhance our ability to identify uranium minerals. Although there is limited chemical information to be gained from the uranium X-ray absorption edges, recent studies have successfully used ligand NEXAFS to study the physical chemistry of various uranium compounds. This study extends the use of ligand NEXAFS to analyze a suite of uranium minerals. We find that major classes of uranyl compounds (carbonate, oxyhydroxide, silicate, and phosphate) exhibit characteristic lineshapes in the oxygen K-edge absorption spectra. As a result, this work establishes a library of reference spectra that can be used to classify unknown uranyl minerals.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1244799
Report Number(s):
PNNL-SA-105197
Journal ID: ISSN 1751-908X; 47772
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Geostandards and Geoanalytical Research (Online); Journal Volume: 40; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
Uranium; X-Ray Absorption; Nuclear Forensics; Spectroscopy; Environmental Molecular Sciences Laboratory

Citation Formats

Ward, Jesse D., Bowden, Mark E., Resch, Charles T., Smith, Steven C., McNamara, Bruce K., Buck, Edgar C., Eiden, Gregory C., and Duffin, Andrew M. Identification of Uranyl Minerals Using Oxygen K-Edge X Ray Absorption Spectroscopy. United States: N. p., 2016. Web. doi:10.1111/j.1751-908X.2015.00337.x.
Ward, Jesse D., Bowden, Mark E., Resch, Charles T., Smith, Steven C., McNamara, Bruce K., Buck, Edgar C., Eiden, Gregory C., & Duffin, Andrew M. Identification of Uranyl Minerals Using Oxygen K-Edge X Ray Absorption Spectroscopy. United States. doi:10.1111/j.1751-908X.2015.00337.x.
Ward, Jesse D., Bowden, Mark E., Resch, Charles T., Smith, Steven C., McNamara, Bruce K., Buck, Edgar C., Eiden, Gregory C., and Duffin, Andrew M. 2016. "Identification of Uranyl Minerals Using Oxygen K-Edge X Ray Absorption Spectroscopy". United States. doi:10.1111/j.1751-908X.2015.00337.x.
@article{osti_1244799,
title = {Identification of Uranyl Minerals Using Oxygen K-Edge X Ray Absorption Spectroscopy},
author = {Ward, Jesse D. and Bowden, Mark E. and Resch, Charles T. and Smith, Steven C. and McNamara, Bruce K. and Buck, Edgar C. and Eiden, Gregory C. and Duffin, Andrew M.},
abstractNote = {Uranium analysis is consistently needed throughout the fuel cycle, from mining to fuel fabrication to environmental monitoring. Although most of the world’s uranium is immobilized as pitchblende or uraninite, there exists a plethora of secondary uranium minerals, nearly all of which contain the uranyl cation. Analysis of uranyl compounds can provide clues as to a sample’s facility of origin and chemical history. X-ray absorption spectroscopy is one technique that could enhance our ability to identify uranium minerals. Although there is limited chemical information to be gained from the uranium X-ray absorption edges, recent studies have successfully used ligand NEXAFS to study the physical chemistry of various uranium compounds. This study extends the use of ligand NEXAFS to analyze a suite of uranium minerals. We find that major classes of uranyl compounds (carbonate, oxyhydroxide, silicate, and phosphate) exhibit characteristic lineshapes in the oxygen K-edge absorption spectra. As a result, this work establishes a library of reference spectra that can be used to classify unknown uranyl minerals.},
doi = {10.1111/j.1751-908X.2015.00337.x},
journal = {Geostandards and Geoanalytical Research (Online)},
number = 1,
volume = 40,
place = {United States},
year = 2016,
month = 3
}
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