Keywords
chlorination, actinide separation, volatilization
Abstract
A purification process involving simultaneous chlorination and volatilization is reported using aluminum, iron, gallium, and uranium separation from cerium metal as the demonstration system. Anhydrous Cl2 gas was reacted with the metal after it had been converted to small particles of hydride at temperatures ranging from 523 to 973 K. Each of the impurities should form chlorides with relatively high saturated vapor pressures. The objective of the process was to volatilize these chlorides after first achieving near-complete conversion of the metals to hydride and then chlorides. Complete conversion of hydrides to chlorides could not be achieved using relatively low-grade (99.5%) Cl2. High decontamination factors for all of the metal impurities required near complete conversion to chloride. It was concluded that oxygen contamination of the feed gas stream likely limits the conversion to chlorides by forming oxides instead, which then limits the volatilization of contaminants. Uranium was particularly challenging to remove in experiments suspected of having high oxygen contamination in the feed gas stream. After switching to ultra-high purity (99.999%) Cl2, complete conversion to chlorides within the measurement error was possible for the entire temperature range studied. Decontamination factors for aluminum, iron, gallium, and uranium were found to have average values of 1.9, 9.8, 14, and 5, respectively, at 973 K. While the process was most extensively studied using a once-through gas flow, recycling unreacted Cl2 gas succeeded at minimizing waste while still maintaining complete conversion and similar decontamination factors.
Original Publication Citation
Parker Okabe, Devin Rappleye, Matthew Newton, Michael F. Simpson, Development of metallic nuclear material purification process via simultaneous chlorination and volatilization, Journal of Nuclear Materials, Volume 543, 2021, 152626, ISSN 0022-3115, https://doi.org/10.1016/j.jnucmat.2020.152626.
BYU ScholarsArchive Citation
Okabe, Parker; Rappleye, Devin; Newton, Matthew; and Simpson, Michael F., "Development of Metallic Nuclear Material Purification Process via Simultaneous Chlorination and Volatilization" (2020). Faculty Publications. 8892.
https://scholarsarchive.byu.edu/facpub/8892
Document Type
Peer-Reviewed Article
Publication Date
2020-10-26
Publisher
Journal of Nuclear Materials
Language
English
College
Ira A. Fulton College of Engineering
Department
Chemical Engineering
Copyright Status
/© 2020 Elsevier B.V. All rights reserved. This is the author's accepted version of this article. The definitive version can be found at https://doi.org/10.1016/j.jnucmat.2020.152626.
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