Abstract
A new bidentate nitrogen donor complexing agent that combines pyridine and triazole functional groups, 2-((4-phenyl-1H-1,2,3-triazol-1-yl)methyl)pyridine (PTMP), has been synthesized. The strength of its complexes with trivalent americium (Am3+) and neodymium (Nd3+) in anhydrous methanol has been evaluated using spectrophotometric techniques. The purpose of this investigation is to assess this ligand (as representative of a class of similarly structured species) as a possible model compound for the challenging separation of trivalent actinides from lanthanides. This separation, important in the development of advanced nuclear fuel cycles, is best achieved through the agency of multidentate chelating agents containing some number of nitrogen or sulfur donor groups. To evaluate the relative strength of the bidentate complexes, the derived constants are compared to those of the same metal ions with 2,2′-bipyridyl (bipy), 1,10-phenanthroline (phen), and 2-pyridin-2-yl-1H-benzimidazole (PBIm). At issue is the relative affinity of the triazole moiety for trivalent f element ions. For all ligands, the derived stability constants are higher for Am3+ than Nd3+. In the case of Am3+ complexes with phen and PBIm, the presence of 1:2 (AmL2) species is indicated. Possible separations are suggested based on the relative stability and stoichiometry of the Am3+ and Nd3+ complexes. It can be noted that the 1,2,3-triazolyl group imparts a potentially useful selectivity for trivalent actinides (An(III)) over trivalent lanthanides (Ln(III)), though the attainment of higher complex stoichiometries in actinide compared with lanthanide complexes may be an important driver for developing successful separations.
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References
Nash, K.L., Madic, C., Mathur, J.N., Lacquement, J. In: Morss, L.R. Edelstein, N.M. Fuger, J. (eds.) The Chemistry of the Actinides and Transactinide Elements, vol. 4, 3rd edn., pp. 2622–2798. Springer, Dordrecht (2006)
Choppin, G.R., Rizkalla, E.N.: Solution chemistry of actinides and lanthanides. In: Gschneider, Jr. K.A., Eyring, L., Choppin, G.R., Lander, G.H. (eds.) Lanthanides/Actinides Chemistry, Handbook on the Physics and Chemistry of Rare Earths, vol. 18, pp. 559–590. Elsevier Science, Amsterdam (1994)
Pearson, R.G.: Hard and soft acids and bases. J. Am. Chem. Soc. 85, 3533–3539 (1963)
Nash, K.L.: Separation chemistry for lanthanides and trivalent actinides. In: Gschneider, Jr. K.A., Eyring, L., Choppin, G.R., Lander, G.H. (eds.) Lanthanides/Actinides Chemistry, Handbook on the Physics and Chemistry of Rare Earths, vol. 18, pp. 197–238. Elsevier Science, Amsterdam (1994)
Musikas, C.: Actinide–lanthanide group separation using sulfur and nitrogen donor extractants. In: Choppin, G.R., Navratil, J.D., Schultz, W.W. (eds.) Actinide/Lanthanide Separations, Proc. Int. Symp., Honolulu, HI, pp. 19–30. World Scientific, Singapore (1985)
Ensor, D.D., Jarvinen, G.D., Smith, B.F.: The use of soft donor ligands 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione and 4,7-diphenyl-1,10-phenanthroline for improved separation of trivalent americium and europium. Solvent Extr. Ion Exch. 6, 439–445 (1988)
Kolarik, Z.: Complexation and separation of lanthanides(III) and actinides(III) by heterocyclic N-donors in solutions. Chem. Rev. 108, 4208–4252 (2008)
Watanabe, M., Mirvaliev, R., Tachimori, S., Takeshita, K., Nakano, Y., Morikawa, K., Chikazawa, T., Mori, R.: Selective extraction of americium(III) over macroscopic concentration of lanthanides(III) by synergistic system of TPEN and D2EHPA in 1-octanol. Solvent Extr. Ion Exch. 22, 377–390 (2004)
Matsumura, T., Takeshita, K.: Extraction behavior of Am(III) from Eu(III) with hydrophobic derivatives of N,N,N′,N′-tetrakis(2-methylpyridyl)ethylenediamine (TPEN). J. Nucl. Sci. Technol. 43, 824–827 (2006)
Drew, M.G.B., Hudson, M.J., Youngs, T.G.A.: QSAR studies of multidentate nitrogen ligands used in lanthanide and actinide extraction processes. J. Alloys Compd. 374, 408–415 (2004)
Hudson, M.J., Foreman, M.R.St.J., Hill, C., Huet, N., Madic, C.: Studies on the parallel synthesis and evaluation of new heterocyclic extractants for the partitioning of minor actinides. Solvent Extr. Ion Exch. 21, 637–652 (2003)
Ogden, M.D.: The effect of structural hindrance on the complexation of actinides and lanthanides by ligands containing soft nitrogen donors. Ph.D. dissertation, Washington State University (August 2009)
Cameron, C.: Enhanced rates of electron transport in conjugated-redox polymer hybrids. Ph.D. dissertation, Memorial University of Newfoundland (2000)
Spencer, L.P., Altwer, R., Wei, P., Gelmini, L., Gauld, J., Stephan, D.W.: Pyridine and imidazole-phosphinimine bidentate ligand complexes: considerations for ethylene oligomerization catalysts. Organometallics 22, 3841–3854 (2003)
Rostovtsev, V.V., Green, L.G., Fokin, V.V., Sharpless, K.B.: A stepwise Huisgen cycloadditon process: copper(I)-catalyzed regioselective “ligation” of azides and terminal alkynes. Angew. Chem., Int. Ed. Engl. 41, 2596–2599 (2002)
Leggett, D.J.: SQUAD: stability quotients from absorbance data. In: Leggett, D.J. (ed.) Computational Methods for the Determination of Formation Constants. Plenum Press, New York (1985). Chap. 6
Sinkov, S.I., Rapko, B.M., Lumetta, G.J., Hay, B.P.: Bicyclic and acyclic diamides: comparison of their aqueous phase binding constants with Nd(III), Am(III), Pu(IV), Np(V), Pu(VI), and U(VI). Inorg. Chem. 43, 8404–8413 (2004)
Martell, A.E., Smith, R.S., Motekaitis, R.J.: NIST Critically Selected Stability Constants of Metal Complexes. NIST Standard Reference Database 46, Version 8.0, Maryland (2004)
Xia, Y.-X., Chen, J.-F., Choppin, G.R.: Solubility, dissociation and complexation with Nd(III) and Th(IV) of oxine, thenoyltrifluoroacetone and 1,10-phenanthroline in 5.0 M NaCl. Talanta 43, 2073–2081 (1996)
Hancock, R.D., Jackson, G., Evers, A.: Affinity of lanthanoid(III) ions for nitrogen-donor ligands in aqueous solution. J. Chem. Soc. Dalton Trans. 9, 1384–1387 (1979)
Thakur, P., Chakravortty, V., Dash, K.C.: Lanthanide(III) complexes with bidentate biheterocyclic ligands. Polyhedron 16, 1417–1424 (1997)
Choppin, G.R.: Comparative solution chemistry of the 4f and 5f elements. J. Alloys Compd. 223, 174–179 (1995)
Miguirditchian, M., Guillaneux, D., Guillaumont, D., Moisy, P., Madic, C., Jensen, M.P., Nash, K.L.: Thermodynamic study of the complexation of trivalent actinide and lanthanide cations by ADPTZ, a tridentate N-donor ligand. Inorg. Chem. 44, 1404–1412 (2005)
Rizkalla, E.N., Sullivan, J.C., Choppin, G.R.: Calorimetric studies of americium(III) complexation by amino carboxylates. Inorg. Chem. 28, 909–911 (1989)
Guillaumont, D.: Quantum chemistry study of actinide(III) and lanthanide(III) complexes with tridentate nitrogen ligands. J. Phys. Chem. A 108, 6893–6900 (2004)
Petit, L., Adamo, C., Maldivi, P.: Toward a clear-cut vision on the origin of 2,6-di(1,2,4-triazin-3-yl)pyridine selectivity for trivalent actinides: insights from theory. Inorg. Chem. 45, 8517–8522 (2006)
Kolb, H.C., Finn, M.G., Sharpless, K.B.: Click chemistry: diverse chemical function from a few good reactions. Angew. Chem. Int. Ed. 40, 2004–2021 (2001)
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This research was conducted at WSU and PNNL with funding provided by the U.S. Department of Energy, Division of Nuclear Energy Science and Technology, Nuclear Energy Research Initiative Consortium (NERI-C) program under project number DE-FG07-07ID14896.
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Ogden, M.D., Hoch, C.L., Sinkov, S.I. et al. Complexation Studies of Bidentate Heterocyclic N-Donor Ligands with Nd(III) and Am(III). J Solution Chem 40, 1874–1888 (2011). https://doi.org/10.1007/s10953-011-9762-7
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DOI: https://doi.org/10.1007/s10953-011-9762-7