Separation of Americium(III) from Europium(III) by Extraction Based on in situ Formation of Dioctylammonium Dioctyldithiocarbamate Extractant

Abstract

In this study an efficient method is developed for removal of minor actinoids (MA) from trivalent rare earth element (RE(III)) ions. An extraction technique is employed that is based on the in situ formation of dioctylammonium dioctyldithiocarbamate (DOA⁺DODTC⁻) as an extractant. This technique has an advantage in that the chemical stability of the extractant need not be taken into consideration. The extraction of Am(III) and Eu(III) from a nitric medium with DOA⁺.DODTC⁻ resulting from carbon disulfide and dioctyl amine in nitrobenzene is studied. The separation factor of Am(III)/Eu(III) is a higher value than that obtained by a cyanex301/kerosene extraction and a similar value with that obtained by a normal extraction of synthesized DOA⁺DODTC⁻/nitrobenzene. The high selectivity for the separation of Am(III) from RE(III) arises from the difference in the reactivity of their metal ions to two sulfur atoms in the functional group of dithiocarbamate.

KEYWORDS:

• in situ extractant formation method
• carbon disulfide
• dioctyl amine
• dioctylammonium dioctyldithiocarbamate
• nitrobenzene
• Am(III)
• Eu(III)
• separation factor