Distribution Behavior of Neptunium by Extraction with N, N-dialkylamides (DEHDMPA and DEHBA) in Mixer-Settler Extractors. Issue 1 (2nd January 2016)

• Record Type: Journal Article
• Authors: Ban, Yasutoshi; Hotoku, Shinobu; Tsutsui, Nao; Tsubata, Yasuhiro; Matsumura, Tatsuro
• Is Part Of: Solvent extraction and ion exchange. Volume 34:Issue 1(2016)
• Page Start: 37
• Page End: 47
• Publication Date: 2016-01-02
• Subjects: N -- N-dialkylamide -- monoamide -- U -- Pu -- Np -- counter-current extraction -- mixer-settler -- reprocessing; Solvent extraction -- Periodicals; Ion exchange -- Periodicals; 660.284248
• DOI: 10.1080/07366299.2015.1130423
• Languages: English
• ISSNs: 0736-6299

Abstract

ABSTRACT: The extraction properties of N, N -di(2-ethylhexyl)-2, 2-dimethylpropanamide (DEHDMPA) and N, N -di(2-ethylhexyl)butanamide (DEHBA) for Np(V) and Np(VI) were studied by a batch method using various nitrate ion concentrations. The distribution ratios of Np(VI) obtained with DEHDMPA and DEHBA exceeded unity when the nitrate ion concentration was > 3 mol/dm 3, while DEHDMPA and DEHBA barely extracted Np(V). A continuous counter-current experiment using mixer-settler extractors was performed to evaluate the behavior of Np in a process comprising two cycles using DEHDMPA and DEHBA as extractants. The feed was nitric acid containing U, Pu, Np, and several fission products. The results indicated that part of Np(V) changed its valence state to Np(IV) or Np(VI) after the 1st experimental cycle. The recoveries of Np in the streams of U fraction and U-Pu fraction were 63.7% and 29.1%, respectively.