EXTRACTION OF ACTINIDES AND SELECTED FISSION PRODUCTS FROM NITRIC ACID MEDIUM USING LONG CHAIN MONOAMIDES

Abstract

A series of long chain disubstituted aliphatic amides have been prepared with different substituting groups and the extracting ability for U(VI), Th(IV) and some fission products like Am(III), Zr(IV), Eu(III) and Cs from nitric acid solutions has been studied. All results were compared with those obtained by using TBP under the same conditions. All prepared amides exhibit higher U-Th separation factors than TBP. Distribution ratios of U(VI) as function of nitric acid concentration, extractants concentration and salting-out agent have been measured by using N,N-dihexyloctanamide (DHOA) and N,N-dihexyl(2-ethyl)hexylhexanamide (DHEHA), which were chosen for further studies. The extraction behviour of U(VI), Th(IV) and Zr(IV) with gamma irradiated DHOA, DHEHA and TBP in toluene from 3 M HNO3 has been studied as a function of absorbed doses. Back extraction of U(VI), Th(IV) and Zr(IV) from organic phases was also studied.