Extraction of Actinide Ion by Asymmetrical N,N′-dimethyl-N,N′-dioctyl-diglycolamide

正In order to develop sustainable nuclear energy,agreat effort has been made for designing new extractants to selectively separate all actinides from nitric acid solutions of dissolution of spent fuel. Among those,tetraalkyldiglyco-     

Extraction of cerium(III) with N,N′-dimethyl-N,N′-dioctyl-diglycolamide in [Bmim][PF6] compared in 40% octanol/kerosene

The extraction of Ce(III) nitrate has been investigated by using N, N′-dimethyl-N, N′-dioctyl-diglycolamide (DMDODGA = L) as extractant with 1-Butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF₆]) as diluent in comparison with 40% octanol/kerosene. DMDODGA in two different diluents shows good extraction ability for Ce(III), but the trends are quite different depending on the concentrations of the ligand in solvent phase and nitric acid in aqueous phase. The slope analysis method is used to obtain the stoichiometric ratio of the extracted complexes. 1:3 complex of Ce(III) to DMDODGA may be formed in both systems, while 1:2 complex may be also formed in DMDODGA-40% octanol/kerosene system. The extraction of Ce(III) is by the cation exchange mechanism in DMDODGA-[Bmim][PF₆] system. Unlike the expected positively charged 1:3 complex of Ce(III) formed in the DMDODGA-40% octanol/kerosene system, the 1:2 complex is assumed to be a neutral complex with two DMDODGA molecules bonding to Ce(III). In addition, the stronger interaction between the C = O groups of L and Ce(III) in the DMDODGA-[Bmim][PF₆] system than in the DMDODGA-40% octanol/kerosene system is confirmed by IR spectroscopy.     

Extraction of lanthanide ions with N,N,N′,N′-tetrabutyl-3-oxadiglycolamide from nitric acid media

Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDGA concentrations,and temperature,on extraction of lanthanide ions were studied.Stoichiometrics of the main extracted species were HNO_3·TBDGA and M(NO_3)_3-3TBDGA(M = Er,Dy,Tb,Gd,La,Ce,Nd,Sm and Eu).The extracted species for metal ions were established to be ionic complex.In this complex,nitrate anion was not coordinated to the central ion.The extraction pattern increased gradually across the lanthanide ions series,showing enhanced affinity of TBDGA toward heavy lanthanide ions.Thermodynamic parameters were investigated for the exothermic extraction reaction.     

N,N′-二甲基-N,N′-二辛基-3-氧戊二酰胺对Np(Ⅳ)的萃取性能研究

正N,N′-二甲基-N,N′-二辛基-3-氧戊二酰胺(DMDODGA)具有能彻底燃烧、耐辐射、不易水解等优点,且该萃取剂具有特殊的三齿配位结构,相对于单齿及双齿萃取剂,其对锕系元素离子有更好的亲合能力,因此备受关注。本工作以40%辛醇-60%煤油为稀释剂,研究了水相平衡硝酸浓度及萃取剂浓度对DMDODGA萃取Np(Ⅳ)的影响及反应机理。在离心管中,取一定体积的水相溶液,加入示踪量的239 Np指示剂(加入过量氨基磺酸亚铁将Np还原至四价),然后加入已预平衡的萃取剂,振荡1h,离心分相后,分别取1 mL有机相和水相,用NaI(γ)谱仪测量     

Theoretical investigation of uranium(Ⅳ) coordinated with N,N'-bis(3-allyl salicylidene)-o-phenylenediamine

We used density functional theory calculations at the B3LYP/6-311G** level for a theoretical study on the complex formed when uranium(Ⅳ) coordinates with N,N'- bis(3-allyl salicylidene)-o-phenylenediamine(BASPDA),i.e.,U(BASPDA)_2.The results indicated that the coordination complex of U(BASPDA)2 could form two different structures with a ratio of 1:2.One was a parallel dislocation structure(PDS-U),in which the two BASPDAs' middle benzene rings adopted a parallel dislocation with an angle of 56.64°,and the other was a staggered finger "+" structure(SFS-U),in which the two BASPDAs employed the staggered finger "+" shape.The binding energies,charge distribution,spectral properties,thermodynamic properties,molecular orbitals and Wiberg bond indices for both PDS-U and SFS-U were calculated and compared with each other.     

Synthesis of N,N＇-dimethyl-N,N＇-didecyl-3-oxa-diglycolamide for extraction of lanthanides

A novel extractant,N,N'-dimethyl-N,N'-didecyl-3-oxa-diglycolamide(DMDDDGA),was designed and synthesized for extraction of lanthanides in the nuclear fuel reprocessing.The extraction behaviors of Gd,Dy,Er and Ho from nitric acid solution were investigated using DMDDDGA in chloroform.The effects of nitric acid concentration,extractant concentration,and temperature on the extraction were investigated.The distribution ratio of lanthanides increases with concentrations of the extractant and nitric acid,but decreases with increasing temperature,which indicates that the extraction process is exothermic.FT-IR spectra indicated that the C=0 in DMDDDGA is coordinated with metal ion in the extracted species and the stoichiometries of lanthanides(Ⅲ)complex are Gd(NO_3)_3·3DMDDDGA,Dy(NO_3)_3·4DMDDDGA,Er(NO_3)_3·4DMDDDGA,and Ho(NO_3)_3·4DMDDDGA.     

Extraction of Lanthanides(Ⅲ) along with Thorium(Ⅳ)from Chloride Solution by N,N-di(2-ethylhexyl)-diglycolamic Acid

<正>The extraction of Nd(Ⅲ),Gd(Ⅲ) and Er(Ⅲ),which represent light,middle and heavy lanthanides,respectively,from chloride solutions has been carried out by using N,N-di(2-ethylhexyl)-diglycolamic acid (HDEHDGA,HA) diluted in kerosene as the organic phase.The results from the slope analysis method indicate that the extraction of Ln(Ⅲ) with HDEHDGA is mainly governed by the cation-exchange reaction mechanisms in the low pH region (pH=1.2-2.7).     

Solubility Studies of Np(Ⅳ) Under Reducing Condition

ThesolubilitiesofNp()insimulatedundergroundwateranddistillwateraremeasuredwiththevariationofpH(6～12),storagetime(0～120d),inthepresenceofreducingagents(Na2S2O4,matallicFe).Allexperimentsareperformedinalowoxygenconcentrationgloveboxwhichcontainedhighpurit…     

Np(Ⅳ)的溶解行为研究

在低氧条件下以Na2S2O4或铁粉作还原剂,测定了Np(Ⅳ）在模拟地下水和重蒸水中的溶解度,讨论了溶液pH值和放置时间对Np(Ⅳ）的形态及在两种水样中溶解度的影响。实验结果表明：放置时间对溶解度的影响不大;随着溶液pH值（6－12）的变化,Np(Ⅳ）在模拟地下水和重蒸水中的溶解度不变,Np(Ⅳ）主要以Np(OH)4,Np(OH)5^-两种形态存在。     

Extraction study of rare earth elements with N,N'-dibutyl–N,N'-di(1-methylheptyl)-diglycolamide from hydrochloric acid

A novel,unsymmetrical diglycolamide,N,N'-dibutyl-N,N'-di(1-methylheptyl)-diglycolamide(DBD1MHDGA),was synthesized.The extraction of rare earth elements(REEs) from a hydrochloric acid medium with DBD1 MHDGA was investigated.The results of the extraction experiments indicated that the distribution ratios of RE(Ⅲ) ions increase with an increase in HC1 concentration,atomic number,and extractant concentration.The calculated thermodynamic data show that the extraction process is an exothermic reaction.The organic phase loaded rare earth ions were characterized by infrared spectroscopy.The composition of the extracted complex was determined.     

DHDECMP萃取Np(Ⅳ)的研究

一、引言 近年来国外不少文献报道了有关双配位基有机磷萃取剂在核燃料后处理中用以回收或清除锕系元素的研究工作,而对这些元素的萃取行为的系统研究报道甚少。在文献[8—10]中,我们用双配位基中性有机磷萃取剂N,N-二乙胺甲酰甲撑膦酸二己酯(简称DHDECMP)对萃取Am(Ⅲ),Pu(Ⅳ),Nd(Ⅲ)和硝酸的各种影响因素及Am(Ⅲ)与Pu(Ⅳ)的分离条件进     

Study on Extraction of Pu(Ⅳ) by Tri-iso-Amyl Phosphate

The extraction performance of Pu(Ⅳ) with tri-iso-amyl phosphate (TiAP) were studied. The effects of the concentration of nitric acid and the ratio of phase on the extraction efficiency of Pu(Ⅳ), and on the     

Syntheses and crystal structures of Eu(III) and Sm(III) perrhenate complexes with 2,2′-(imino)bis(N,N′-diethylacetamide)

Europium(III) and Sm(III) perrhenate complexes with 2,2′-(imino)bis(N,N′-diethyl-acetamide) (IDEA) were synthesized. From the single crystal X-ray analyses, the synthesized complexes were found to be [Eu(IDEA)₃][Eu(NO₃)₄(ReO₄)₂]_0.38[Eu(NO₃)₅(ReO₄)]_0.62 (I) and [Sm(IDEA)₃][Sm(NO₃)₄ (ReO₄)₂]_0.23[Sm(NO₃)₅(ReO₄)]_0.77 (II). In the cationic parts [M(IDEA)₃]³⁺ (M = Eu and Sm), M(III) is nine-coordinated with three tridentate IDEA ligands. The anionic parts are located crystallographically at the same position in the unit cell. The occupancies of [M(NO₃)₄(ReO₄)₂]^3? and [M(NO₃)₅(ReO₄)]^3? are 38% and 62% for Eu(III), 23% and 77% for Sm(III), respectively. The main crystallographic parameters are as follows: space group P2₁/c, unit cell parameters a = 12.3811 (4) Å, b = 32.0748 (8) Å, c = 16.7287 (4) Å, β = 112.358 (1)°, Z = 4, V = 6143.9 (3) ų for (I), and space group P2₁/c, unit cell parameters a = 12.3597 (2) Å, b = 32.1599 (6) Å, c = 16.6762 (4) Å, β = 112.431 (1)°, Z = 4, V = 6127.0 (2) ų for (II). Infrared (IR) absorption spectra of the complexes I and II support the coordination of IDEA and ReO₄^? to M(III) through each carbonyl oxygen and one oxygen.     

氟化镧沉淀载带法测定Np(Ⅲ,Ⅳ)和Np(V,Ⅵ)的含率

一、引言有关氟化镧载带法测定Pu(Ⅲ,Ⅳ)和Pu(Ⅴ,Ⅵ)含率的放化分析方法已有报道,方法在实际应用中被证明是可靠有效的。一般都认为氟化镧沉淀能载带三价和四价镎,不载带六价镎,但它对五价镎的载带行     

反相分配色层-阴离子交换法分离测定Np(Ⅳ)、Np(Ⅴ)、Np(Ⅵ)

本文研究了用TBP反相分配色层法分离、测定Np(Ⅳ、Ⅴ、Ⅵ)的条件,并对纯Np硝酸体系或U-Np硝酸体系进行Np(Ⅳ、Ⅴ、Ⅵ)的测定。此法简单快速。用反相分配色层—阴离子交换法分离、测定了低浓铀高燃耗料液中Np的各种价态的比例。本文对Np(Ⅵ)在色层柱上的还原问题进行了研究,掌握了某些规律,并寻得了解决的方法。     

用萃取色层法分离Np(Ⅳ),NP(Ⅴ)和Np(Ⅵ)

本文研究了用磷酸三(2—乙基己基)酯(以下简称为TIOP)作固定相、硝酸等为流动相的萃取色层法在分离Np(Ⅳ)、Np(Ⅴ)和Np(Ⅵ)中的应用。利用Np(Ⅳ)、Np(Ⅴ)和Np(Ⅵ)在TIOP—硅胶柱上分配系数的差异使不同价态的镎得到分离。Np(Ⅴ)不被TIOP吸附,Np(Ⅳ)、Np(Ⅵ)分别用HNO_3+HF、HNO_3+HF+Fe(NH_2SO_3)_2洗脱,从而达到定量分离。文中并对光的影响进行了讨论。最后简单叙述了用TIOP—萃淋树脂来分离Np(Ⅳ)、Np(Ⅴ)和Np(Ⅵ)的实验。     

二氧化碳和腐殖酸对Np(Ⅳ)、Tc(Ⅳ)溶解度影响研究

正在高放地质处置的低氧条件下,Np(Ⅳ)、Tc(Ⅳ)等可能在地下水中发生水解反应,以溶解度很低的水解产物形式存在而不易迁移,但地下水中的二氧化碳和腐殖酸也可能与这些水解产物作用,生成溶解度较大的物质,使低价态的Np、Tc等也容易发生迁移。本研究在低氧(O_2浓度小于     

N,N-二甲基-3-氧杂-戊酰胺酸与Np(Ⅳ),Pu(Ⅳ)配合物稳定常数的测定

应用溶剂萃取法研究了N，N-二甲基-3-氧杂-戊酰胺酸(DOGA)与Np(Ⅳ)，Pu(Ⅳ)的配位行为。研究结果表明，DOGA与Np(Ⅳ)，Pu(Ⅳ)在25℃可以形成比较稳定的配合物，配合物的逐级累积稳定常数分别为：Pu(DOGA)3^ ：1gβ1=6．52，1gβ2=9．14，1gβ3=15．77；Np(DOGA)3^ ：1gβ1=6．95，1gβ2=10．435，1gβ3=14．93。     

Extraction of uranyl（VI）ion with N,N—dibutyloctadecanamide from nitric acid solution

The extraction of U(VI) with newly synthesized long chain alkyl amide,N,N-dibutyloctadecanamide(DBODA),has been studied.The dependence of the extraction on nitric acid concentration,DBODA concentration and temperature from nitric acid solution has been investigated and the extracted species has also been investigated using FT-IR spectrometry.The related thermodynamic functions were calculated.The separation factor between U(VI) and Th(IV) is higher and there is no third phase formation under the conditions studied.