Abstract
In support of nuclear safeguards and nonproliferation efforts, Oak Ridge National Laboratory is responsible for characterizing uranium ore concentrate (UOC) samples obtained from two ore mining and milling sites. A sorptive extraction method has been developed for analysis of non-volatile organic compounds that might be used to identify characteristics of the purification process by which uranium was separated from these ores. This method utilizes Gerstel Twister- stir bars coated with polydimethylsiloxane to extract organic components from aqueous media. A slurry of UOC is extracted with the Twister- stir bar in 20 % methanol/80 % water containing deuterated internal hydrocarbon standards. Following extraction of non-volatile organics, the Twister- stir bar is analyzed directly in the inlet of a gas chromatograph fitted with a quadrupole mass spectrometric detector. Results have been consistent and have shown excellent recoveries of internal standards, with the average recovery being 97.5 %. Both qualitative and quantitative differences have been identified between the two sources of UOC utilizing this method. One source contained an increased concentration of amines which commonly are used in the recovery and purification of ores. Amines that were identified in this UOC source include dioctylamine, triisoctylamine, and Alamine- 336, a common industrial complexant. Also, when comparing both sources, the same UOC source contained various decanol and C20 compounds. Based on the results from this study, non-volatile organic analysis of UOC using sorptive extraction with Twister- stir bars and GC-MS is a tool that can be used to facilitate sourcing of unknown UOC.
| Original language | English |
|---|---|
| Pages (from-to) | 817-821 |
| Number of pages | 5 |
| Journal | Journal of Radioanalytical and Nuclear Chemistry |
| Volume | 296 |
| Issue number | 2 |
| DOIs | |
| State | Published - May 2013 |
Funding
Acknowledgments This work was sponsored by the Department of Energy, National Nuclear Security Administration, Office of Non-proliferation and International Security (NA-24) under contract DE-AC05-00OR22725 in conjunction with Oak Ridge National Laboratory managed and operated by UT-Battelle, LLC. The submitted manuscript has been authored by a contractor of the US Government under contract no. DE-AC05-00OR22725. Accordingly, the US Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes.
Keywords
- GC-MS
- Nuclear forensics
- Sorptive extraction
- Twister- stir bar
- Uranium ore concentrate