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Mezyk SP, Baxter M, Celis-Barros C, Grimes TS, Zalupski PR, Rae C, Zarzana CA, Cook AR, Horne GP. Effect of f-element complexation on the radiolysis of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]). Dalton Trans 2024; 53:6881-6891. [PMID: 38407412 DOI: 10.1039/d4dt00424h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
A systematic study of the impact on the chemical reactivity of the oxidising n-dodecane radical cation (RH˙+) with f-element complexed 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) has been undertaken utilizing time-resolved electron pulse radiolysis/transient absorption spectroscopy and high-level quantum mechanical calculations. Lanthanide ion complexed species, [Ln((HEH[EHP])2)3], exhibited vastly increased reactivity (over 10× faster) in comparison to the non-complexed ligand in n-dodecane solvent, whose rate coefficient was k = (4.66 ± 0.22) × 109 M-1 s-1. Similar reactivity enhancement was also observed for the corresponding americium ion complex, k = (5.58 ± 0.30) × 1010 M-1 s-1. The vastly increased reactivity of these f-element complexes was not due to simple increased diffusion-control of these reactions; rather, enhanced hole transfer mechanisms for the complexes were calculated to become energetically more favourable. Interestingly, the observed reactivity trend with lanthanide ion size was not linear; instead, the rate coefficients showed an initial increase (Lu to Yb) followed by a decrease (Tm to Ho), followed by another increase (Dy to La). This behaviour was excellently predicted by the calculated reaction volumes of these complexes. Complementary cobalt-60 gamma irradiations for select lanthanide complexes demonstrated that the measured kinetic differences translated to increased ligand degradation at steady-state timescales, affording ∼38% increase in ligand loss of a 1 : 1 [La((HEH[EHP])2)3] : HEH[EHP] ratio system.
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Affiliation(s)
- Stephen P Mezyk
- Department of Chemistry and Biochemistry, California State University Long Beach, Long Beach, CA 90804, USA.
| | - Makayla Baxter
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Center for Radiation Chemistry Research, Idaho National Laboratory, Idaho Falls, ID, P.O. Box 1625, 83415, USA.
| | | | - Travis S Grimes
- Center for Radiation Chemistry Research, Idaho National Laboratory, Idaho Falls, ID, P.O. Box 1625, 83415, USA.
| | - Peter R Zalupski
- Center for Radiation Chemistry Research, Idaho National Laboratory, Idaho Falls, ID, P.O. Box 1625, 83415, USA.
| | - Cathy Rae
- Center for Radiation Chemistry Research, Idaho National Laboratory, Idaho Falls, ID, P.O. Box 1625, 83415, USA.
| | - Christopher A Zarzana
- Center for Radiation Chemistry Research, Idaho National Laboratory, Idaho Falls, ID, P.O. Box 1625, 83415, USA.
| | - Andrew R Cook
- Department of Chemistry, Brookhaven National Laboratory, Upton, New York, 11973, USA
| | - Gregory P Horne
- Center for Radiation Chemistry Research, Idaho National Laboratory, Idaho Falls, ID, P.O. Box 1625, 83415, USA.
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Summers TJ, Sobrinho JA, de Bettencourt-Dias A, Kelly SD, Fulton JL, Cantu DC. Solution Structures of Europium Terpyridyl Complexes with Nitrate and Triflate Counterions in Acetonitrile. Inorg Chem 2023; 62:5207-5218. [PMID: 36940386 DOI: 10.1021/acs.inorgchem.3c00199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2023]
Abstract
Lanthanide-ligand complexes are key components of technological applications, and their properties depend on their structures in the solution phase, which are challenging to resolve experimentally or computationally. The coordination structure of the Eu3+ ion in different coordination environments in acetonitrile is examined using ab initio molecular dynamics (AIMD) simulations and extended X-ray absorption fine structure (EXAFS) spectroscopy. AIMD simulations are conducted for the solvated Eu3+ ion in acetonitrile, both with or without a terpyridyl ligand, and in the presence of either triflate or nitrate counterions. EXAFS spectra are calculated directly from AIMD simulations and then compared to experimentally measured EXAFS spectra. In acetonitrile solution, both nitrate and triflate anions are shown to coordinate directly to the Eu3+ ion forming either ten- or eight-coordinate solvent complexes where the counterions are binding as bidentate or monodentate structures, respectively. Coordination of a terpyridyl ligand to the Eu3+ ion limits the available binding sites for the solvent and anions. In certain cases, the terpyridyl ligand excludes any solvent binding and limits the number of coordinated anions. The solution structure of the Eu-terpyridyl complex with nitrate counterions is shown to have a similar arrangement of Eu3+ coordinating molecules as the crystal structure. This study illustrates how a combination of AIMD and EXAFS can be used to determine how ligands, solvent, and counterions coordinate with the lanthanide ions in solution.
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Affiliation(s)
- Thomas J Summers
- Department of Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada 89557-0388, United States
| | - Josiane A Sobrinho
- Department of Chemistry, University of Nevada, Reno, Reno, Nevada 89557-0705, United States
| | | | - Shelly D Kelly
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439-4801, United States
| | - John L Fulton
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - David C Cantu
- Department of Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada 89557-0388, United States
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3
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Zhang J, Wenzel M, Schnaars K, Hennersdorf F, Lindoy LF, Weigand JJ. Highly Tunable 4-Phosphoryl Pyrazolone Receptors for Selective Rare-Earth Separation. Inorg Chem 2023; 62:3212-3228. [PMID: 36752766 DOI: 10.1021/acs.inorgchem.2c04221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Highly selective rare-earth separation has become increasingly important due to the indispensable role of these elements in various cutting-edge technologies including clean energy. However, the similar physicochemical properties of rare-earth elements (REEs) render their separation very challenging, and the development of new selective receptors for these elements is potentially of very considerable economic and environmental importance. Herein, we report the development of a series of 4-phosphoryl pyrazolone receptors for the selective separation of trivalent lanthanum, europium, and ytterbium as the representatives of light, middle, and heavy REEs, respectively. X-ray crystallography studies were employed to obtain solid-state structures across 11 of the resulting complexes, allowing comparative structure-function relationships to be probed, including the effect of lanthanide contraction that occurs along the series from lanthanum to europium to ytterbium and which potentially provides a basis for REE ion separation. In addition, the influence of ligand structure and lipophilicity on lanthanide binding and selectivity was systematically investigated via n-octanol/water distribution and liquid-liquid extraction (LLE) studies. Corresponding stoichiometry relationships between solid and solution states were well established using slope analyses. The results provide new insights into some fundamental lanthanide coordination chemistry from a separation perspective and establish 4-phosphoryl pyrazolone derivatives as potential practical extraction reagents for the selective separation of REEs in the future.
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Affiliation(s)
- Jianfeng Zhang
- Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, Dresden 01062, Germany
| | - Marco Wenzel
- Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, Dresden 01062, Germany
| | - Kathleen Schnaars
- Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, Dresden 01062, Germany
| | - Felix Hennersdorf
- Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, Dresden 01062, Germany
| | - Leonard F Lindoy
- School of Chemistry, F11, University of Sydney, New South Wales 2006, Sydney, Australia
| | - Jan J Weigand
- Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, Dresden 01062, Germany.,Department of Chemistry and Polymer Science, Stellenbosch University, Stellenbosch 7600, South Africa
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Graham TR, Castillo J, Sinkov S, Gelis AV, Lumetta GJ, Cho H. Multiplicity of Th(IV) and U(VI) HEH[EHP] Chelates at Low Temperatures from Concentrated Nitric Acid Extractions. Inorg Chem 2023; 62:792-801. [PMID: 36584069 DOI: 10.1021/acs.inorgchem.2c03307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Organophosphorus extractants have been widely investigated for lanthanide recovery from ore and for application in the reprocessing of spent nuclear fuel, such as in Advanced TALSPEAK schemes. Determining the speciation of the extracted metal complex in the organic phase remains a significant challenge. A better understanding of the variability of HEH[EHP]-actinide complexes and the speciation of chelates for tetra- and hexavalent actinides can improve the predictability of actinide phase transfer in such biphasic systems. In this study, the extraction of Th(IV) and U(VI) from nitric acid media using HEH[EHP] in heptane is examined. The distribution ratio as a function of nitric acid concentration was quantified using UV-vis spectroscopy, and then the speciation of HEH[EHP]-metal complexes in the organic phase was investigated using Fourier transform infrared (FTIR) spectroscopy and low-temperature 31P nuclear magnetic resonance (NMR) spectroscopy. In addition to perturbation of the vibrational modes proximal to the phosphonic moiety in HEH[EHP] in the FTIR spectra, the appearance of a nitrate signal was found in the organic phase following extraction from the highest acidity conditions for U(VI). The 31P NMR spectra of the organic phase at a low temperature (-70 °C) exhibited a surprising number (n) of resonances (n ≥ 7 for Th(IV) and n ≥ 11 for U(VI)), with the distribution between these resonances changing with the initial concentration of nitric acid in the aqueous phase. These results indicate that the compositions of the inner and outer spheres of the extracted actinides in the organic phase are more diverse than initially thought.
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Affiliation(s)
- Trent R Graham
- Pacific Northwest National Laboratory, RichlandWashington99354, United States
| | - Joel Castillo
- Radiochemistry Program University of Nevada, Las Vegas, Las VegasNevada89154, United States
| | - Sergey Sinkov
- Pacific Northwest National Laboratory, RichlandWashington99354, United States
| | - Artem V Gelis
- Radiochemistry Program University of Nevada, Las Vegas, Las VegasNevada89154, United States
| | - Gregg J Lumetta
- Pacific Northwest National Laboratory, RichlandWashington99354, United States
| | - Herman Cho
- Pacific Northwest National Laboratory, RichlandWashington99354, United States
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Hirata S, Kusaka R, Meiji S, Tamekuni S, Okudera K, Hamada S, Sakamoto C, Honda T, Matsushita K, Muramatsu S, Ebata T, Kajiya D, Saitow KI, Ikeda T, Hirao T, Haino T, Watanabe M, Inokuchi Y. Lanthanide and Actinide Ion Complexes Containing Organic Ligands Investigated by Surface-Enhanced Infrared Absorption Spectroscopy. Inorg Chem 2023; 62:474-486. [PMID: 36548946 DOI: 10.1021/acs.inorgchem.2c03618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A new technique, surface-enhanced infrared absorption (SEIRA) spectroscopy, was used for the structural investigation of lanthanide (Ln) and actinide (An) complexes containing organic ligands. We synthesized thiol derivatives of organic ligands with coordination sites similar to those of 2-[N-methyl-N-hexanethiol-amino]-2-oxoethoxy-[N',N'-diethyl]-acetamide [diglycolamide (DGA)], Cyanex-272, and N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN), which have been used for separating Ln and An through solvent extraction. These ligands were attached on a gold surface deposited on an Si prism through S-Au covalent bonds; the gold surface enhanced the IR absorption intensity of the ligands. Aqueous solutions of Ln (Eu3+, Gd3+, and Tb3+) and An (Am3+) ions were loaded onto the gold surface to form ion complexes. The IR spectra of the ion complexes were obtained using Fourier transform infrared spectroscopy in the attenuated total reflection mode. In this study, we developed a new sample preparation method for SEIRA spectroscopy that enabled us to obtain the IR spectra of the complexes with a small amount of ion solution (5 μL). This is a significant advantage for the IR measurement of radiotoxic Am3+ complexes. In the IR spectra of DGA, the band attributed to C═O stretching vibrations at ∼1630 cm-1 shifted to a lower wavenumber by ∼20 cm-1 upon complexation with Ln and An ions. Moreover, the amount of the red shift was inversely proportional to the extraction equilibrium constant reported in previous studies on solvent extraction. The coordination ability of DGA toward Ln and An ions could be assessed using the band position of the C═O band. The Cyanex-272- and TPEN-like ligands synthesized in this report also showed noticeable SEIRA signals for Ln and An complexes. This study indicates that SEIRA spectroscopy can be used for the structural investigation of ion complexes and provides a microscopic understanding of selective extraction of Ln and An.
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Affiliation(s)
- Sakiko Hirata
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Ryoji Kusaka
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki319-1195, Japan
| | - Shogo Meiji
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Seita Tamekuni
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Kosuke Okudera
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Shoken Hamada
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Chihiro Sakamoto
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Takumi Honda
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Kosuke Matsushita
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Satoru Muramatsu
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Takayuki Ebata
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Daisuke Kajiya
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Ken-Ichi Saitow
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Toshiaki Ikeda
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Takehiro Hirao
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Takeharu Haino
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
| | - Masayuki Watanabe
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki319-1195, Japan
| | - Yoshiya Inokuchi
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima739-8526, Japan
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Verma PK, Karak A, Sahu P, Aswal VK, Mahanty B, Ali SM, Egberink RJM, Huskens J, Verboom W, Mohapatra PK. Aggregation Behavior of Nitrilotriacetamide (NTAmide) Ligands in Thorium(IV) Extraction from Acidic Medium: Small-Angle Neutron Scattering, Fourier Transform Infrared, and Theoretical Studies. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:14745-14759. [PMID: 36394314 DOI: 10.1021/acs.langmuir.2c02394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Two tripodal amides obtained from nitrilotriacetic acid with n-butyl and n-octyl alkyl chains (HBNTA(LI) and HONTA(LII), respectively) were studied for the extraction of Th(IV) ions from nitric acid medium. The effect of the diluent medium, i.e., n-dodecane alone and a mixture of n-dodecane and 1-decanol, onto aggregate formation were investigated using small angle neutron scattering (SANS) studies. In addition, the influence of the ligand structure, nitric acid, and Th(IV) loading onto ligand aggregation and third-phase formation tendency was discussed.The LI/LII exist as monomers (aggregarte radius for LI: 6.0 Å; LII:7.4 Å) in the presence of 1-decanol, whereas LII forms dimers (aggregarte radius for LII:9.3 Å; LI does not dissolve in n-dodecane) in the absence of 1-decanol. The aggregation number increases for both the ligands after HNO3 and Th(IV) loading. The maximum organic concentration (0.050 ± 0.004 M) of Th(IV) was reached without third-phase formation for 0.1 M LI/LII dissolved in 20% isodecanol +80% n-dodecane. The interaction of 1-decanol with LII and HNO3/Th(IV) with amidic oxygens of LI/LII results in shift of carbonyl stretching frequency, as shown by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) studies. The structural and bonding information of the Th-LI/LII complex were derived from the density functional theoretical (DFT) studies. The molecular dynamics (MD) simulations suggested that the aggregation behavior of the ligand in the present system is governed by the population of hydrogen bonds by phase modifier around the ligand molecules. Although the theoretical studies suggested higher Gibbs free energy of complexation for Th4+ ions with LI than LII, the extraction was found to be higher with the latter, possibly due to the higher lipophilicity and solubility of the Th-LII aggregate in the nonpolar media.
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Affiliation(s)
- Parveen K Verma
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai400094, India
| | - Ananda Karak
- Homi Bhabha National Institute, Anushaktinagar, Mumbai400094, India
- INRPO, FF, Nuclear Recycle Board, Bhabha Atomic Research Centre, Tarapur, Mumbai400085, India
| | - Pooja Sahu
- Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai91400085, India
| | - Vinod K Aswal
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai400085, India
| | - Bholanath Mahanty
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai400094, India
| | - Sk Musharaf Ali
- Homi Bhabha National Institute, Anushaktinagar, Mumbai400094, India
- Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai91400085, India
| | - Richard J M Egberink
- Laboratory of Molecular Nanofabrication, Department for Molecules & Materials, MESA+ Institute, University of Twente, P.O. Box 217, 7500 AEEnschede, The Netherlands
| | - Jurriaan Huskens
- Laboratory of Molecular Nanofabrication, Department for Molecules & Materials, MESA+ Institute, University of Twente, P.O. Box 217, 7500 AEEnschede, The Netherlands
| | - Willem Verboom
- Laboratory of Molecular Nanofabrication, Department for Molecules & Materials, MESA+ Institute, University of Twente, P.O. Box 217, 7500 AEEnschede, The Netherlands
| | - Prasanta K Mohapatra
- Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai400085, India
- Homi Bhabha National Institute, Anushaktinagar, Mumbai400094, India
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7
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Picayo GA, Etz BD, Eddy MA, Vyas S, Jensen MP. Characterization of the ALSEP Process: Investigating Equilibrium and Intermediate Complexes of the Scrub Stage. SOLVENT EXTRACTION AND ION EXCHANGE 2022. [DOI: 10.1080/07366299.2022.2037222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Brian D. Etz
- Chemistry Department, Colorado School of Mines, Golden, Colorado, USA
| | - Madeleine A. Eddy
- Chemistry Department, Colorado School of Mines, Golden, Colorado, USA
| | - Shubham Vyas
- Chemistry Department, Colorado School of Mines, Golden, Colorado, USA
| | - Mark P. Jensen
- Chemistry Department, Colorado School of Mines, Golden, Colorado, USA
- Nuclear Science and Engineering Program, Colorado School of Mines, Golden, Colorado, USA
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Mattocks JA, Cotruvo JA, Deblonde GJP. Engineering lanmodulin's selectivity for actinides over lanthanides by controlling solvent coordination and second-sphere interactions. Chem Sci 2022; 13:6054-6066. [PMID: 35685815 PMCID: PMC9132084 DOI: 10.1039/d2sc01261h] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 04/25/2022] [Indexed: 11/21/2022] Open
Abstract
Developing chelators that combine high affinity and selectivity for lanthanides and/or actinides is paramount for numerous industries, including rare earths mining, nuclear waste management, and cancer medicine. In particular, achieving selectivity between actinides and lanthanides is notoriously difficult. The protein lanmodulin (LanM) is one of Nature's most selective chelators for trivalent actinides and lanthanides. However, mechanistic understanding of LanM's affinity and selectivity for f-elements remains limited. In order to decipher, and possibly improve, the features of LanM's metal-binding sites that contribute to this actinide/lanthanide selectivity, we characterized five LanM variants, substituting the aspartate residue at the 9th position of each metal-binding site with asparagine, histidine, alanine, methionine, and selenomethionine. Spectroscopic measurements with lanthanides (Nd3+ and Eu3+) and actinides (243Am3+ and 248Cm3+) reveal that, contrary to the behavior of small chelator complexes, metal-coordinated water molecules enhance LanM's affinity for f-elements and pH-stability of its complexes. Furthermore, the results show that the native aspartate does not coordinate the metal directly but rather hydrogen bonds to coordinated solvent. By tuning this first-sphere/second-sphere interaction, the asparagine variant nearly doubles LanM's selectivity for actinides versus lanthanides. This study not only clarifies the essential role of coordinated solvent for LanM's physiological function and separation applications, but it also demonstrates that LanM's preference for actinides over lanthanides can be further improved. More broadly, it demonstrates how biomolecular scaffolds possess an expanded repertoire of tunable interactions compared to most small-molecule ligands – providing an avenue for high-performance LanM-based actinide/lanthanide separation methods and bio-engineered chelators optimized for specific medical isotopes. Nature’s most potent protein for f-elements, lanmodulin, relies on subtle first-sphere/second-sphere interactions to bind metal ions. Dissecting lanmodulin’s binding mechanism yielded variants with enhanced actinide/lanthanide selectivity.![]()
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Affiliation(s)
- Joseph A. Mattocks
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Joseph A. Cotruvo
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Gauthier J.-P. Deblonde
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
- Glenn T. Seaborg Institute, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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9
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Kimberlin A, Saint-Louis G, Guillaumont D, Camès B, Guilbaud P, Berthon L. Effect of Metal Complexation on Diglycolamides Radiolysis: A Comparison between Ex-Situ Gamma and In-Situ Alpha Irradiation. Phys Chem Chem Phys 2022; 24:9213-9228. [DOI: 10.1039/d1cp05731f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Radiolytic degradation is an important aspect to consider when developping a ligand or a complexant for radionucleides. Diglycolamide extractants (DGAs) have been playing an important role in many partition processes...
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10
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Prathibha T, Rama Swami K, Suneesh A, Robert Selvan B, Sriram S, Venkatesan K. Extraction and aggregation behaviour of Zr(IV) in diglycolamide solvents during the treatment of high-level liquid waste solution arising from metallic fuel reprocessing. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Špadina M, Dourdain S, Rey J, Bohinc K, Pellet-Rostaing S, Dufrêche JF, Zemb T. How acidity rules synergism and antagonism in liquid–liquid extraction by lipophilic extractants—Part II: application of the ienaic modelling. SOLVENT EXTRACTION AND ION EXCHANGE 2021. [DOI: 10.1080/07366299.2021.1899614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- M. Špadina
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
- Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
| | - S. Dourdain
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
| | - J. Rey
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
| | - K. Bohinc
- Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
| | | | | | - T. Zemb
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
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12
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Cantu DC. Predicting lanthanide coordination structures in solution with molecular simulation. Methods Enzymol 2021; 651:193-233. [PMID: 33888204 DOI: 10.1016/bs.mie.2021.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The chemical and physical properties of lanthanide coordination complexes can significantly change with small variations in their molecular structure. Further, in solution, coordination structures (e.g., lanthanide-ligand complexes) are dynamic. Resolving solution structures, computationally or experimentally, is challenging because structures in solution have limited spatial restrictions and are responsive to chemical or physical changes in their surroundings. To determine structures of lanthanide-ligand complexes in solution, a molecular simulation approach is presented in this chapter, which concurrently considers chemical reactions and molecular dynamics. Lanthanide ion, ligand, solvent, and anion molecules are explicitly included to identify, in atomic resolution, lanthanide coordination structures in solution. The computational protocol described is applicable to determining the molecular structure of lanthanide-ligand complexes, particularly with ligands known to bind lanthanides but whose structures have not been resolved, as well as with ligands not previously known to bind lanthanide ions. The approach in this chapter is also relevant to elucidating lanthanide coordination in more intricate structures, such as in the active site of enzymes.
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Affiliation(s)
- David C Cantu
- Department of Chemical and Materials Engineering, University of Nevada, Reno, Reno, NV, United States.
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Dourdain S, Špadina M, Rey J, Bohinc K, Pellet-Rostaing S, Dufrêche JF, Zemb T. How Acidity Rules Synergism and Antagonism in Liquid–Liquid Extraction by Lipophilic Extractants—Part I: Determination of Nanostructures and Free Energies of Transfer. SOLVENT EXTRACTION AND ION EXCHANGE 2021. [DOI: 10.1080/07366299.2021.1899606] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- S. Dourdain
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
| | - M. Špadina
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
- Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
| | - J. Rey
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
| | - K. Bohinc
- Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
| | | | | | - T. Zemb
- ICSM, Univ Montpellier, CEA, CNRS, ENSCM, Marcoule, France
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Shiery RC, Fulton JL, Balasubramanian M, Nguyen MT, Lu JB, Li J, Rousseau R, Glezakou VA, Cantu DC. Coordination Sphere of Lanthanide Aqua Ions Resolved with Ab Initio Molecular Dynamics and X-ray Absorption Spectroscopy. Inorg Chem 2021; 60:3117-3130. [PMID: 33544594 DOI: 10.1021/acs.inorgchem.0c03438] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
To resolve the fleeting structures of lanthanide Ln3+ aqua ions in solution, we (i) performed the first ab initio molecular dynamics (AIMD) simulations of the entire series of Ln3+ aqua ions in explicit water solvent using pseudopotentials and basis sets recently optimized for lanthanides and (ii) measured the symmetry of the hydrating waters about Ln3+ ions (Nd3+, Dy3+, Er3+, Lu3+) for the first time with extended X-ray absorption fine structure (EXAFS). EXAFS spectra were measured experimentally and generated from AIMD trajectories to directly compare simulation, which concurrently considers the electronic structure and the atomic dynamics in solution, with experiment. We performed a comprehensive evaluation of EXAFS multiple-scattering analysis (up to 6.5 Å) to measure Ln-O distances and angular correlations (i.e., symmetry) and elucidate the molecular geometry of the first hydration shell. This evaluation, in combination with symmetry-dependent L3- and L1-edge spectral analysis, shows that the AIMD simulations remarkably reproduces the experimental EXAFS data. The error in the predicted Ln-O distances is less than 0.07 Å for the later lanthanides, while we observed excellent agreement with predicted distances within experimental uncertainty for the early lanthanides. Our analysis revealed a dynamic, symmetrically disordered first coordination shell, which does not conform to a single molecular geometry for most lanthanides. This work sheds critical light on the highly elusive coordination geometry of the Ln3+ aqua ions.
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Affiliation(s)
- Richard C Shiery
- Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada 89557, United States
| | - John L Fulton
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | | | - Manh-Thuong Nguyen
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Jun-Bo Lu
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Roger Rousseau
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | | | - David C Cantu
- Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada 89557, United States
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M. Pallares R, Hébert S, Sturzbecher-Hoehne M, Abergel RJ. Chelator-assisted high performance liquid chromatographic separation of trivalent lanthanides and actinides. NEW J CHEM 2021. [DOI: 10.1039/d1nj01966j] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
3,4,3-LI(1,2-HOPO) can be used as a HPLC chelating agent, promoting lanthanide and trivalent actinide separation without column modifications.
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Affiliation(s)
- Roger M. Pallares
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - Solène Hébert
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | | | - Rebecca J. Abergel
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Nuclear Engineering
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16
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Countercurrent Actinide Lanthanide Separation Process (ALSEP) Demonstration Test with a Simulated PUREX Raffinate in Centrifugal Contactors on the Laboratory Scale. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10207217] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
An Actinide Lanthanide Separation Process (ALSEP) for the separation of trivalent actinides (An(III)) from simulated raffinate solution was successfully demonstrated using a 32-stage 1 cm annular centrifugal contactor setup. The ALSEP solvent was composed of a mixture of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) and N,N,N′,N′-tetra-(2-ethylhexyl)-diglycolamide (T2EHDGA) in n-dodecane. Flowsheet calculations and evaluation of the results were done using the Argonne’s Model for Universal Solvent Extraction (AMUSE) code using single-stage distribution data. The co-extraction of Zr(IV) and Pd(II) was prevented using CDTA (trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid) as a masking agent in the feed. For the scrubbing of co-extracted Mo; citrate-buffered acetohydroxamic acid was used. The separation of An(III) from the trivalent lanthanides (Ln(III)) was achieved using citrate-buffered diethylene-triamine-N,N,N′,N″,N″-pentaacetic acid (DTPA), and Ln(III) were efficiently back extracted using N,N,N′,N′-tetraethyl-diglycolamide (TEDGA). A clean An(III) product was obtained with a recovery of 95% americium and curium. The Ln(III) were efficiently stripped; but the Ln(III) product contained 5% of the co-stripped An(III). The carryover of Am and Cm into the Ln(III) product is attributed to too few actinide stripping stages, which was constrained by the number of centrifugal contactors available. Improved separation would be achieved by increasing the number of An strip stages. The heavier lanthanides (Pr, Nd, Sm, Eu, and Gd) and yttrium were mainly routed to the Ln product, whereas the lighter lanthanides (La and Ce) were mostly routed to the raffinate.
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