Related Experiment Video
Updated: Jun 9, 2025

Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films
Published on: November 9, 2015
An insightful study on the reduction and extraction of neptunium assisted by molybdenum
Huaixin Hao1, Yaoyang Liu1, Hong Cao1
1Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China. wangzhipeng@mail.tsinghua.edu.cn.
Abstract:
High-level liquid waste (HLLW) generated through nuclear reactions and spent fuel reprocessing contains the critical transuranic element neptunium (Np). Thus, the efficient recovery of Np from HLLW via the TRPO (trialkylphosphine oxide) process is not only beneficial for radioactive contamination remediation but also boosts the recycling of precious nuclear resources. However, this process including Np(V)-Np(IV) conversion is highly dependent on the components coexisting in HLLW, and its underlying mechanism is still not clear, restricting the recovery of Np in multiple scenarios. Herein, the effect of coexisting metal ions on the reduction and extraction of Np(V) was studied, and molybdenum (Mo) was identified to play a vital role in this course. Additionally, in combination with absorption spectral analysis, X-ray photoelectron spectroscopy and solvent extraction, the promotion of the extraction of Np by Mo was elucidated to be due to the catalytic reduction effect both in the aqueous phase and organic phase. This study can help researchers better understand the redox chemistry of Np in the treatment of HLLW.
Related Concept Videos
Nuclear Transmutation
Nuclear Overhauser Enhancement (NOE)
Nuclear Fission
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)

