Abstract
ABSTRACTRouting neptunium to a single product in spent nuclear fuel reprocessing is a significant challenge. In this work, we have further improved the simulation of neptunium extraction in an advanced PUREX flowsheet by applying a revised model of the Np(V)–Np(VI) redox reaction kinetics, a new nitric acid radiolysis model, and by evaluating various models for the nitrous acid distribution coefficient. The Np disproportionation reaction is shown to have a negligible effect. The models are validated against published ‘cold test’ experimental results; the ‘hot test’ simulation suggests that high neptunium radiolysis could help to achieve high recoveries using this flowsheet.
Highlights
Nuclear energy plays an important role in the supply of sustainable and secure electricity
The simulation of the hot test shows that the nitrous acid yield through radiolysis can improve the neptunium extraction in the advanced PUREX process and that 99% of neptunium would still be routed to the organic product when radiolysis occurs
The hot test simulation results indicate the likely influences of radiolysis on neptunium extraction under radiation conditions that will be present when reprocessing spent nuclear fuel
Summary
Nuclear energy plays an important role in the supply of sustainable and secure electricity. Based on the research of neptunium redox in aqueous-only phase and two-phase extractions,[11,22] a revised description of neptunium kinetics is applied in this work to improve the simulation model. During this reaction, the role of nitrous acid is important: it catalyzes oxidation at low concentrations, but acts as a reductant at high concentrations, reducing Np(VI) to Np(V). The effects of the disproportionation reaction of Np(V) were evaluated and are reported in this article
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
