The comparative characteristic of methods partitioning HLW in Russia for transmutation of radionuclides

Methods of recovery long-lived radionuclides from HLLW with the purpose more safe isolation from environment and transmutation the most toxic radionuclides, are considered. For separation of minor actinoids and fission products are offered extraction, membrane extraction, ion-exchange chromatographic, precipitation and pyrometallurgical methods with use neutral monodentate and polydentate compounds including carbonyl, amide and phosphoryl groups, phosphorus-organic acids and their salts, cobalt chlorinated dicarbollyde. The basic problems, arising by use of phosphorus-organic acids (POA) for isolate of pure fractions of minor actinoids from HLW, are discussed. Opportunity of use new extractant on a basis of acid zirconium compounds salts (ZCS) of POA for partitioning HLW is shown. Acid zirconium compounds salts (ZCS) of HDEHP and n-alkyl(C8C10) phenyl-phosphonic acid may be used for deep extraction of TPE and other α-nuclides from HLW with concentration up to 2 mol/I HNO3. The extraction process of long-lived radionuclides from the solutions, characterized by complex salt composition and high radioactivity level, can be fulfilled by two successive stages. In case ZCS of HDEHP on first stages we separated light REE and TPE, on the two stages REE yttrium group. Scheme of TPE, Ln and 90Sr extraction with simultaneous removal of other α-nuclides from HLW includes TPE and Ln extraction with 0,9 mol/I n-alkyl(C8-C10)phenyl-phosphonic acid solution in n-paraffin dissolvent and 90Sr extraction with 0,15 mol/I solution of zirconium salt of the indicated acid. The perspective approach by choice of technology partitioning consists in combined extraction, sorption and precipitation methods for preparation radionuclides to transmutation. The minimization of secondary waste of partitioning is connected with development of new selective reagents, methods of multistage processes organization and also physical methods separation. (authors)