Synthesis and Extraction Properties of First Representatives of 2-(Phosphorylamido)-Substituted 1,8-Naphthyridines

摘要

Liquid radioactive waste, which is formed in large amounts in the process of spent fuel treatment, is a serious environmental hazard since it contains considerable amounts of long-lived radionuclides, mainly radioactive isotopes of f elements, actinides and lanthanides [1]. One of the most promising methods of liquid waste treatment is extraction with the use of different types of organic and organoelement compounds as extractants. Organoelement extractants of greatest interest are neutral organophosphorus ligands, first of all, bidentate ones, capable of efficiently extracting tetra- and hexavalent actinides from acid media. Unfortunately, these ligands are, as a rule, considerably less efficient in extraction of trivalent actinides and lanthanides [2]. At the same time, it was shown that trivalent actinides (for example, americium and curium) can be efficiently extracted from acid media by means of various polydentate nitrogen-containing hetero-cycles, such as tripyridyltriazines, terpyridines, bis(benz-imidazolyl)pyridines, bis(benzothiazolyl)pyridines, and especially polyalkyl-substituted 2,6-bis(1,2,4-triazin-3-yl)pyridines [3-5].