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6. Understanding the Role of Ligand Structure on Extraction of Neptunium by N-Pivot Tripodal Diglycolamides in an Ionic Liquid.

Author

Gujar, Rajesh B., Ansari, Seraj A., Mohapatra, Prasanta K., and Verboom, Willem

Subjects
*METHYL groups, *LIGANDS (Chemistry), *ALKYL group, *IONIC liquids, *NEPTUNIUM
Abstract

The extraction of Np4+ was studied by a series of N-pivot tripodal diglycolamides, with varying substituents (alkyl groups with varying branching and chain length) and varying spacer length, dissolved in an ionic liquid, i.e. [C4mim][Tf2N]. Out of a series of four ligands, LI (propylene spacer) and LII (ethylene spacer) differ only in the spacer length connecting the three diglycolamide units with the tripodal N platform. While LII – LIV have the same spacer length (ethylene spacer), but LII has a hydrogen atom, LIII has methyl group, and LIV has isopropyl group as a substituent at the amidic N atom close to the central N atom. A reversal extraction mechanism of Np4+ was observed when the spacer chain length reduced from a propylene group in LI to an ethylene group in LII – LIV. While a cation-exchange mechanism was observed in case of LI, a solvation extraction mechanism was seen for the other three ligands with the extracted species being Np(NO3)2(L)2+ for LI, and [Np(NO3)4·L] for LII – LIV. The extraction efficiencies of Np4+ with LII – LIV were significantly affected by the nature of the alkyl substituents and follow the order: LII > LIII > LIV. This trend in the extraction pattern affirms that the alkyl substitution at the amidic N atom creates steric strain in the ligand while complexing with the metal ion. [ABSTRACT FROM AUTHOR]

Published
2024
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20. First Report on a 1-Cycle Solid-Phase Extraction Method for Selective Separation of Am3+and Eu3+: Use of BTP-Grafted Silica Decorated on Activated Carbon

Author

Ansari, Seraj A., Gujar, Rajesh B., Bhattacharyya, Arunasis, Thangaraj, Bharathkumar, Natesan Sundaramurthy, Karthikeyan, Ravichandran, Cingaram, Toleti, Subba Rao, and Mohapatra, Prasanta K.

Abstract

A new composite sorbent material was prepared by grafting bis-triazinylpyridine (BTP) onto silica and then blending it with activated charcoal (AC–Si–BTP) for the selective separation of Am3+over Eu3+using a 1-cycle solid-phase extraction for the direct separation of lanthanides from actinides. BTP was attached to silica via a sulfonamide bond between R–BTP and amino silane, and the resulting Si–BTP was covalently bonded to activated carbon (AC) with a favorable orientation of the ligand coordination sites. The material exhibited a significantly large distribution coefficient for Am3+over Eu3+at lower acidities (<0.5 M HNO3), and the separation factor between the two metal ions was found to be maximum in 0.2 M HNO3with a value of 110. The loading capacity of the material was 4.05 ± 0.12 mg of Eu per gram of the composite when investigated at pH 3. The radiation stability of the material was excellent when studied up to an absorbed dose of 1000 kGy. The material was tested for the separation of Am3+and Eu3+in a column mode, which gave selective loading of Am3+over Eu3+. The reusability studies indicated slow leaching of the BTP fraction from the solid, with a resultant decrease of the Kdvalues with time. To address this issue, the material was embedded in polysulfone beads for a separate set of studies, but the separation efficiencies were found to be comparable.

Published
2024
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40. Highly efficient actinide(III)/lanthanide(III) separation by novel pillar[5]arene-based picolinamide ligands: A study on synthesis, solvent extraction and complexation

Author

Cai, Yimin, primary, Ansari, Seraj A., additional, Fu, Kuirong, additional, Zhu, Beichen, additional, Ma, Haoyang, additional, Chen, Lixi, additional, Conradson, Steven D., additional, Qin, Song, additional, Fu, Haiying, additional, Mohapatra, Prasanta K., additional, Yuan, Lihua, additional, and Feng, Wen, additional

Published
2021
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43. Isolation of single crystals of a homoleptic UO22+-diglycolamide complex from a room temperature ionic liquid: X-ray crystallography and complexation studies.

Author

Ansari, Seraj A., Wadawale, Amey P., Verboom, Willem, and Mohapatra, Prasanta K.

Subjects
*IONIC liquids, *SINGLE crystals, *X-ray crystallography, *COMPLEX ions
Abstract

Complexation and structural investigations of the solid complex of UO22+ ions and N,N,N′,N′-tetramethyl diglycolamide isolated from a room temperature ionic liquid, for the first time, revealed that the nature and the structural features of the complex are identical to those of the complex isolated from an aqueous medium. [ABSTRACT FROM AUTHOR]

Published
2022
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44. Highly Efficient Extraction of Trivalent f ‐Cations Using Several N ‐Pivot Tripodal Diglycolamide Ligands in an Ionic Liquid: The Role of Ligand Structure on Metal Ion Complexation

Author

Ansari, Seraj A., primary, Mohapatra, Prasanta K., additional, Verma, Parveen K., additional, Leoncini, Andrea, additional, Yadav, Ashok K., additional, Jha, Shambhu N., additional, Bhattacharyya, Dibyendu, additional, Huskens, Jurriaan, additional, and Verboom, Willem, additional

Published
2020
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49. Unfolding the complexation and extraction of Am3+ and Eu3+ using N-heterocyclic aromatic diphosphonic acids: a combined experimental and DFT study

Author

Bhattacharyya, Arunasis, primary, Ansari, Seraj A., additional, Matveev, Petr I., additional, Zakirova, Gladis G., additional, Borisova, Nataliya E., additional, Petrov, Vladimir G., additional, Sumyanova, Tsagana, additional, Verma, Parveen Kumar, additional, Kalmykov, Stepan N., additional, and Mohapatra, Prasanta Kumar, additional

Published
2019
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