Exploring the complexation behaviour of NpO with diglycolamide in ionic liquid aqueous solution.

The complexation of NpO with tetramethyl diglycolamide (TMDGA) was investigated in an ionic liquid (IL: 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide, Bumim.TfN), with the objective of understanding its complexation behaviour and optical properties in both IL and aqueous media. We successfully prepared the NpO(TfN) salt, and its complexation with TMDGA was studied using absorption spectroscopy.

Radiation stability of two extraction chromatography resins containing aza-crown-based diglycolamides used for Am(III) uptake.

The radiolytic stability of two extraction chromatography resins with multiple diglycolamide arms was investigated by exposing them to gamma radiation and carrying out uptake studies of Am(III) from acidic feeds. The resins contained aza-crown-based diglycolamide (DGA) ligands, viz., triaza-9-crown-3-N,N',N"-trisdiglycolamide (TAM-3-DGA) and tetraaza-12-crown-4-N,N',N",N'"-tetrakisdiglycolamide (TAM-4-DGA), where the DGA moieties were grafted to the 'N' atoms of the macrocyclic ring.

Effect of branching in the alkyl chain of diglycolamide on the sequestration of tetravalent actinides: solvent extraction and theoretical studies.

DGA (diglycolamide) ligands show a different extraction behavior of trivalent metal ions by changing the branching alkyl chain length as well as the branching at the methylene position. There are no studies of these factors on the extraction efficiency of these DGA derivatives for the extraction of tetravalent actinides. We have evaluated four different DGA derivatives for the extraction of Np, Pu, and Th from molecular diluents.

Remarkable Improvement in Am and Cm Separation Using a Cooperative Counter Selectivity Strategy by a Combination of Branched Diglycolamides and Hydrophilic Polyaza-heterocycles.

Separation of Am and Cm is one of the most challenging problems in the back-end of the nuclear fuel cycle. In the present work, we exploited the cooperative effect of the opposite selectivity of hydrophobic branched DGA derivatives and hydrophobic N-donor heterocyclic ligands taken in two different phases to achieve improved separation behavior. A systematic study was performed using a series of DGA derivatives to understand the effect and the position of branching in the alkyl chains on the separation behavior of Am and Cm.

A comparative study on the uptake of lanthanides from acidic feeds using extraction chromatography resins containing N,N,N',N'-tetra-n-alkyl diglycolamides with varying alkyl chain lengths in an ionic liquid.

A comparative study on the uptake of several rare earth element (REE) ions viz. La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III) and Dy(III) was carried out from nitric acid feeds using four extraction chromatography resins which contained the diglycolamide (DGA) ligands, N,N,N',N'-tetra-n-alkyldiglycolamide with n-pentyl (TPDGA), n-hexyl (THDGA), n-octyl (TODGA) and n-decyl (TDDGA) groups taken in a room temperature ionic liquid (Cmim·NTf). The uptake of the lanthanides followed the trend: La(III) < Ce(III) < Pr(III) < Nd(III) < Sm(III) < Gd(III) < Dy(III), which is similar to their ionic potential values and the uptake trend of the resins was TPDGA > THDGA > TODGA > TDDGA.

Radiation stability of two extraction chromatography resin materials containing substituted diglycolamide ligands in an ionic liquid.

The radiation stability of two extraction chromatography resins containing diglycolamide ligands viz. TPDGA (N,N,N',N'-tetra-n-pentyl diglycolamide) and TODGA (N,N,N',N'-tetra-n-octyl diglycolamide) in a room temperature ionic liquid (Cmim.NTf) was studied by exposing to gamma rays from a Co source.

Stability of composite polymeric beads containing a calix[4]arene-mono-crown-6 ligand for radio-cesium separation.

Bis-octyloxy-calix[4]arene-mono-crown-6 (BOCMC) is a selective ligand for Cs(I) cation, and has been used in solvent extraction method for its separation from acidic feed. Looking at the various advantages and ease of extraction chromatography separation method, an attempt was made to prepare stable composite beads containing BOCMC entrapped in a suitable polymeric matrix. Therefore, an attempt was made to prepare a series of composite polymeric beads containing BOCMC in polysulfone (PS), polyether sulfone (PES) and sodium alginate polymeric matrix.

Highly efficient uptake of Europium (III) and Americium (III) from acidic feeds using extraction chromatography resins containing N,N,N',N'-tetra alkyl diglycolamides with varying alkyl chain length in an ionic liquid.

A comparative study on the uptake of Eu(III) and Am(III) was carried out using four extraction chromatography (XC) resins impregnated with constant weight of the tetra-n-pentyl diglycolamide (TPDGA) ligands, viz. tetra-n-hexyl diglycolamide (THDGA), tetra-n-octyl diglycolamide (TODGA) and tetra-n-decyl diglycolamide (TDDGA) along with Cmim·NTf, a room temperature ionic liquid (RTIL), from nitric acid feed solutions. The uptake of Eu(III) was higher than that of Am(III) while the uptake trend with the four XC resins followed the order: TPDGA > THDGA > TODGA > TDDGA, which was opposite to the alkyl chain length attached to the DGA extractant.

Highly efficient uptake of tetravalent actinide ions from nitric acid feeds using an extraction chromatography material containing tetra-n-butyl diglycolamide and a room temperature ionic liquid.

An extraction chromatography (XC) material containing N,N,N',N'-tetra-n-butyl diglycolamide (TBDGA) and 1-butyl-3-methylimidazolium bis(trifluoromethanesulphonyl) imide (Cmim∙NTf), a room temperature ionic liquid, was used for the uptake of the tetravalent actinide ions Th(IV), Np(IV), and Pu(IV) from nitric acid feed solutions. The uptake of the metal ions followed the trend: Th(IV) < Np(IV) < Pu(IV), which is the same as that of their ionic potential values. While a decrease in the Np(IV) and Pu(IV) uptake was seen with increasing HNO concentration at lower acidities, an opposite trend was observed at higher acidities.

Selective uptake of thorium(IV) from nitric acid medium using two extraction chromatographic resins based on diglycolamide-calix[4]arenes: Application to thorium-uranyl separation in an actual sample.

Two novel extraction chromatography resins (ECRs) containing two diglycolamide (DGA) -functionalized calix[4]arenes with n-propyl and isopentyl substituents at the amide nitrogen atom, termed as ECR-1 and ECR-2, respectively, were evaluated for the uptake of Th(IV) from nitric acid feed solutions. While both the resins were having a quite high Th(IV) uptake ability (K >3000 at 3 M HNO), the uptake was relatively lower with the resin containing the isopentyl DGA, which appeared magnified at lower nitric acid concentrations. Kinetic modeling of the sorption data suggested fitting to the pseudo-second order model pointing to a chemical reaction during the uptake of the metal ion.

Highly efficient uptake of neptunium from acidic feeds using two solid phase extraction resins containing diglycolamide-functionalized calix[4]arene ligands.

Two solid phase extraction resins (SPER) were prepared by impregnating solutions of two diglycolamide-functionalized calix[4]arenes in 10% isodecanol in n-dodecane into Chromosorb W, as the stationary phase. While SPER-I contained n-propyl functionalized calix[4]arene, SPER-II contained the calix[4]arene with isopentyl groups at the carboxamide nitrogen atoms. The SPERs were characterized by SEM, TGA, FTIR, etc.

Comparative uptake studies on trivalent f-cations from acidic feeds using two extraction chromatography resins containing a diglycolamide in molecular diluent and ionic liquid.

Low molecular weight diglycolamide (DGA) extractants were tested for the extraction of europium(III) and americium(III) from nitric acid solutions in n-dodecane, a molecular diluent and 1-butyl-3-methylimidazolium bis(trifluoromethanesulphonyl) imide (Cmim⋅NTf), a room temperature ionic liquid, as the diluents. N,N,N',N'-tetra-n-butyl diglycolamide (TBDGA) was selected for extraction chromatography (XC) studies involving Eu(III) and Am(III). While the TBDGA resin containing n-dodecane gave reasonably high K values, that containing the ionic liquid showed higher Eu(III) uptake values.

Actinide ion uptake from acidic radioactive feeds using an extraction chromatographic resin containing a branched dialkyl amide.

A dialkyl amide with branched alkyl group, viz. N,N-di(2-ethylhexyl)-propionamide (D2EHPrA) was used as the organic extractant in an extraction chromatographic resin prepared for the first time and evaluated for the separation of uranium from acidic feeds. The distribution coefficient measurements, carried out at varying HNO concentrations, indicated an increase in the UO ion sorption with increasing nitric acid concentration.

Two novel extraction chromatographic resins containing benzene-centered tripodal diglycolamide ligands: Actinide uptake, kinetic modeling and isotherm studies.

Two novel extraction chromatographic resins (EC), termed as RL-1 and RL-2, were prepared by impregnating two benzene-centered tripodal iglycolamide ligands (Bz-T-DGA) containing different spacer groups where the ligands are termed as L-1 and L-2, respectively. They were employed for the uptake of actinide and fission product ions, viz. Am, Eu, UO, Np, Pu, Sr, and Cs, from acidic feeds.

Superparamagnetic graphene oxide-magnetite nanoparticle composites for uptake of actinide ions from mildly acidic feeds.

Super paramagnetic graphene oxide (GO) - FeO nanoparticle composites were prepared and characterized by conventional techniques such as XRD, SEM, EDX, FT-IR, Raman, XPS, DLS and zeta potential, etc. TEM studies have confirmed nanoparticle nature of the composites. The GO-magnetic nanoparticle composites can be dispersed in mildly acidic aqueous solutions and get concentrated in a small volume under application of an external magnetic field.

Complexation of tetraalkyl diglycolamides with trivalent f-cations in a room temperature ionic liquid: extraction and spectroscopic investigations.

This paper reports the complexation of a series of tetraalkyl diglycolamides (TRDGA) with trivalent f-cations in a room temperature ionic liquid, viz., 3-octyl-1-methylimidazolium bis(trifluoromethanesulfonyl)imide ([Cmim][TfN]). The stability constants of TRDGA/Nd complexes (where R = n-pentyl, n-hexyl, n-octyl, n-decyl and 2-ethylhexl) were determined by absorbance spectroscopy.