Studies on the extraction of actinides by diamylamyl phosphonate

Diamylamyl phosphonate (DAAP) was synthesised by the Michealis Becker reaction, and was characterized by elemental analysis, IR, and P-31 NMR. The extraction of U(VI), Th(IV), Pu(IV) and Am(III) by 1.1 MDAAP in n-dodecane as a function of nitric acid concentration was studied and the results are compared with the extraction behavior of these ions by tributyl phosphate (TBP) and triamyl phosphate (TAP) in n-dodecane. Some important physical properties of the extractant that have to be met for its use in industrial scale liquid-liquid extraction such as density, surface tension, viscosity and phase disengagement time with 1.1 M DAAP/n-dodecane have been measured and compared with those of 1.1 M TBP/n-dodecane. Studies on the third phase formation behavior of DAAP/n-dodecane with U(VI) and Th(IV) nitrates in nitric acid medium have been carried out and the results are reported. The breakthrough and elution behavior of U(VI) using a column packed with 50% (w/w) DAAP impregnated on Amberlite XAD-7 was studied and reported.