ИСТИНА

Development of high-tech separation of REE and minor actinides (Am, Cm, Np) in the processing of HLW in the construction of a closed nuclear fuel cycle and to produce high-purity rare earth compounds are among the strategic objectives of the country. Creating highly selective extractants for such processes is a challenge due to the exceptional similarity of chemical properties of these 4f- and 5f- elements. Quantum-chemical modeling (DFT, ab initio functional PBE and hybrid functionals PBE (0) and B3LYP, relativistic full electron TZ-basis, PRIRODA code) used to simulate structures and properties of lanthanide complexes and actinides with several series of N-heterocyclic ligands containing oxygen and nitrogen donor centers. Structures 1, 2, 3 and 4 having the highest characteristics (selectivity factors, thermodynamic stability of complexes) were selected as basic platforms for the synthesis. The synthesis of series of selected compounds with various substituents R and X, and their complexes with lanthanides has been performed. The ligands and complexes were characterized by UV-vis, IR, NMR, MS and XRD. The results of theoretical prediction verified in the extraction experiments on the model systems. The prospects of the use of new extractants in the development of viable technologies are discussed. [1]. Yu. A. Ustynyuk, N. E. Borisova, V. A. Babain, I. P. Gloriozov, A. Y. Manuilov, S. N. Kalmykov, M.Yu. Alyapyshev, L. I. Tkachenko, E. V. Kenf, and N. A. Ustynyuk, Chemical Communications, 2015, 51(35), 7466-7469. [2]. Yu. A. Ustynyuk, I. P. Gloriozov, S N. Kalmykov, A.A. Mitrofanov, V. A. Babain, M.Yu. Alyapyshev, N.A. Ustynyuk, Solvent Extraction and Ion Exchange, 2014, 32: 508–528.