An Insightful Study on the Reduction and Extraction of Neptunium Assisted by Molybdenum
(Note: The full text of this document is currently only available in the PDF Version )
Huai Xin Hao , Yaoyang Liu , Hong Cao , Zhipeng Wang , Chao Xu and Jing Chen
First published on 10th October 2024
Abstract
High level liquid waste (HLLW) generated through nuclear reaction and spent fuel reprocessing contains the critical transuranic element, neptunium (Np). Efficient recovery of Np from HLLW via TRPO (trialkyl phosphine oxide) process not only benefits radioactive contamination remediation, but also boosts precious nuclear resources recycling. However, such a process including Np(V)-Np(IV) conversion is highly dependent on the coexisting components in HLLW yet the underlying mechanism is still not clear, which adversely restricts Np recovery in multiple scenarios. Herein, effect of concomitant metal ions on the reduction and extraction of Np(V) was studied and molybdenum (Mo) was identified as the vital role in this course. Additionally, in combination with absorption spectral analysis, X-ray photoelectron spectroscopy and solvent extraction, the promotion in the extraction of Np by Mo is elucidated as the catalytic reduction both in the aqueous phase and the organic phase. This study can help us better understand the redox chemistry of Np in the treatment of HLLW.