TY - JOUR
T1 - Role of ligand spacer length of a tripodal amide on uranium(vi) and plutonium(iv) complexation
T2 - synthesis, solvent extraction, liquid membrane transport and theoretical studies
AU - Karak, Ananda
AU - Mahanty, Bholanath
AU - Mohapatra, Prasanta K.
AU - Musharaf Ali, Sk.
AU - Egberink, Richard J.M.
AU - Sathe, Darshan B.
AU - Bhatt, Raj B.
AU - Valsala, Thisur P.
AU - Huskens, Jurriaan
AU - Verboom, Willem
N1 - Funding Information:
The computer division, BARC, is acknowledged for providing the Anupam supercomputing facility. SMA sincerely thanks Mr K. T. Shenoy, Director, Chemical Engineering Group, BARC for continuous encouragement.
Publisher Copyright:
© 2022 The Royal Society of Chemistry.
PY - 2022/10/20
Y1 - 2022/10/20
N2 - Liquid-liquid extraction of several actinide and lanthanide ions, viz., U(vi), Pu(iv), Am(iii) and Eu(iii) was investigated from nitric acid feed solutions employing N,N,N′,N′,N′′,N′′-hexa-n-octyl nitrilotripropamide (HONTP) in 90% n-dodecane + 10% isodecanol. The observed trend of metal ion extraction at 0.5 M HNO3 was Pu(iv) > U(vi) > Eu(iii) ∼ Am(iii). A high distribution ratio was observed for U(vi) at pH 2 using 0.08 M HONTP in 90% n-dodecane + 10% isodecanol. The back extraction study of Pu(iv) and U(vi) using 0.5 M HNO3 + 0.5 M oxalic acid and 1 M Na2CO3, respectively, showed highly efficient stripping (>97%) for both the metal ions from the loaded organic phase. Slope analysis suggested formation of a lower stoichiometry complex of Pu(iv) with HONTP at 3 M HNO3, whereas U(vi) formed 1 : 1 (ML) and 1 : 2 (ML2) species. Temperature variation studies on the extraction of the metal ions showed that complexation of U(vi) with HONTP was not favourable, based on entropy changes. A supported liquid membrane study showed very poor transport of U(vi) using 0.08 M HONTP in 90% n-dodecane + 10% isodecanol, whereas Pu(iv) exhibited significant transport through the membrane. Density functional theoretical (DFT) studies were carried out to corroborate the experimental observations. Comparison of the results with those of hexa-n-octyl nitrilotriacetamide (HONTA) revealed a considerable effect of the spacer length on the binding efficiency, selectivity, and complex stoichiometry.
AB - Liquid-liquid extraction of several actinide and lanthanide ions, viz., U(vi), Pu(iv), Am(iii) and Eu(iii) was investigated from nitric acid feed solutions employing N,N,N′,N′,N′′,N′′-hexa-n-octyl nitrilotripropamide (HONTP) in 90% n-dodecane + 10% isodecanol. The observed trend of metal ion extraction at 0.5 M HNO3 was Pu(iv) > U(vi) > Eu(iii) ∼ Am(iii). A high distribution ratio was observed for U(vi) at pH 2 using 0.08 M HONTP in 90% n-dodecane + 10% isodecanol. The back extraction study of Pu(iv) and U(vi) using 0.5 M HNO3 + 0.5 M oxalic acid and 1 M Na2CO3, respectively, showed highly efficient stripping (>97%) for both the metal ions from the loaded organic phase. Slope analysis suggested formation of a lower stoichiometry complex of Pu(iv) with HONTP at 3 M HNO3, whereas U(vi) formed 1 : 1 (ML) and 1 : 2 (ML2) species. Temperature variation studies on the extraction of the metal ions showed that complexation of U(vi) with HONTP was not favourable, based on entropy changes. A supported liquid membrane study showed very poor transport of U(vi) using 0.08 M HONTP in 90% n-dodecane + 10% isodecanol, whereas Pu(iv) exhibited significant transport through the membrane. Density functional theoretical (DFT) studies were carried out to corroborate the experimental observations. Comparison of the results with those of hexa-n-octyl nitrilotriacetamide (HONTA) revealed a considerable effect of the spacer length on the binding efficiency, selectivity, and complex stoichiometry.
KW - UT-Hybrid-D
KW - 2023 OA procedure
UR - http://www.scopus.com/inward/record.url?scp=85141473087&partnerID=8YFLogxK
U2 - 10.1039/d2nj03354b
DO - 10.1039/d2nj03354b
M3 - Article
AN - SCOPUS:85141473087
VL - 46
JO - New journal of chemistry
JF - New journal of chemistry
SN - 1144-0546
IS - 44
M1 - 21221-21228
ER -