REDOX BEHAVIOUR OF NEPTUNIUM IN PUREX EXTRACTION PROCESSES

PUREX 萃取过程中镎的氧化还原行为

• 批准号: 03453166
• 负责人: INOUE Yasushi
• 金额: $ 4.16万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03453166/
• 关键词: neptunium; nitrous acid; nitric acid; Purex process; solvent extraction; TBP; oxidation; kinetics

In order to clarify the distribution behavior of neptunium in the Purex extraction processes, the equilibrium and rate of the extraction of neptunium into 30% TBP-dodecane were examined as a function of nitrous acid (3-6 M) and nitrous acid (10^<-4>-10^<-2> M) concentrations. It was shown that the rapid equilibrium between nitric and nitrous acids controlls the redox potential of the aqueous phase, which in turn controlls the ratio of the concentrations of extractable Np(VI) to unextractable Np(V). The redox potential can be quantitatively described with using the activities of nitric acid, nitrous acid and water in nitric acid solutions:E/V = 0.951 + 0.058・log<@D7{HNO<@D23@>D2}<@D12@>D1(/){HNO<@D22@>D2}<@D11/2@>D1{H<@D22@>D2O}<@D11/2@>D1@>D7 By examining also the rate of the extraction of neptunium into TOPO-dodecane, the ratedetermining step was confirmed to be the oxidation of Np(V) to Np(VI) in the aqueous phase. The rate of the reaction was obtained to be:k/h = 5.44 x {HNO_3}^<1.02>{HNO_2}^<0.56>

为了澄清纯X提取过程中的Neptunium的分布行为，检查了30％tbp-dodecane的分布，作为亚硝酸（3-6 m）和亚硝酸的功能（10^ <-4> -10^ <-2） > m）浓度表明，氮酸之间的快速平衡控制了deox sepe的氧化还原电位，这又控制了可提取的NP（VI）的浓度与不可摘要的NP（V）。通过使用硝酸的活化率进行定量，itric Acid溶液：E/V = 0.951 + 0.058 log <@d7 {hno <@d23@> d2@> d2} <@d12@> d12@> d1@> d1（/）{hno d2} <@d11/2@> d1 {h <{h> d2o} <@d11/2@>@> d7，还检查了extinium to dododecane的速率。 ：k/ h = 5.44 x {hno_3}^<1.02> {hno_2}^<0.56>

项目成果

井上 泰: "ピュレックス工程におけるネプツニウムの酸化還元挙動" 日本原子力学会 1991年秋の大会講演要旨集.

Yasushi Inoue：“Purex 过程中镎的氧化还原行为”日本原子能学会 1991 年秋季会议摘要。

井上 泰: "ピュレックス工程におけるネプツニウムの酸化還元挙動" 日本原子力学会1991年秋の大会講演要旨集. 674 (1991)

Yasushi Inoue：“Purex 过程中镎的氧化还原行为”日本原子能学会 1991 年秋季会议摘要 674 (1991)。

Y.Inoue,O. Tochiyama and Y.Nakamura: "Redox Behavior of Neptunium in Purex Extraction Process" 1991 Fall Meeting of the Atomic Energy Society of Japan. 674 (1991)

井上，O.