Potentiality of Nonorganophosphorus Extractant in Chemical Separations of Actinides

Abstract

Abstract To limit the amounts of radioactive wastes coming from actinide separations by solvent—extraction, completely incinerable extractants are desirable. This paper deals with the prospects offered by N, N-dialkylamide.s, as alternatives to TBP for irradiated nuclear fuels reprocessing and by N, N'-tetraalkyl 2-alkylpro-pane diamides as actinide extractants from radioactive wastes solutions. The selection of N. N'-dialkylamides based on the solubility of the nitrato-uranyl amide complexes in aliphatic hydrocarbons is presented. The extraction chemistry of the main metallic ions present in irradiated nuclear fuels nitrate solutions is discussed as well as the hydrolysis and radio-lysis of these extractants. Results of a bench scale test for a first reprocessing cycle shows the reason for interest in the N, N-dialkylamides as substitutes for TBP. The extraction of the main metallic species contained in actinide wastes by N, N'-tetraalkylpropane diamide or by N, N'-tetraalkyl, 2-alkylpropane diamide is p...