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DOE OSTI · 2573936

Investigating Radiation-Induced Actinide Species in Solution

Kynman, Amy Elizabeth [Idaho National Laboratory] (ORCID:0000000345325792)·Holmbeck, Gregory Peter [Idaho National Laboratory] (ORCID:0000000305960660)·Grimes, Travis S [Idaho National Laboratory] (ORCID:0000000327510492)
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Abstract

Our fundamental understanding of actinide radiation-induced redox chemistry is crucial due to their unavoidable exposure to ionizing radiation fields, both inherent and from in-process applications. Plutonium (Pu) and americium (Am) both possess multiple oxidation states, the careful manipulation of which are essential in the study and utilization of their rich chemistry, developing new nuclear technologies, and securing the long-term sustainability of nuclear power. However, knowledge in this area is far from complete. Consequently, we have studied the radiation-induced chemistry of both Pu and Am through a variety of techniques. Temperature-controlled electron pulse radiolysis has been used to study Am for the first time, determining the feasibility of Am redox reactions under used nuclear fuel reprocessing conditions, (e.g. nitric acid, non-ambient temperature). Additionally, we developed an experimentally evaluated multi-scale computer model for the prediction of gamma radiation-induced Pu redox chemistry due to radiolysis and disproportionation reactions in concentrated nitric acid solutions.

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actinideamericiummultiscale modelplutoniumpulse radiolysisradiation chemistryredox

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Kynman, Amy Elizabeth [Idaho National Laboratory] (ORCID:0000000345325792), Holmbeck, Gregory Peter [Idaho National Laboratory] (ORCID:0000000305960660), Grimes, Travis S [Idaho National Laboratory] (ORCID:0000000327510492). 2025-03-25. Investigating Radiation-Induced Actinide Species in Solution. https://www.osti.gov/biblio/2573936

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