Extraction behavior of uranium, plutonium and some fission products with gamma-irradiated N. N'-dialkylamides

The extraction behavior of U(VI), Pu(IV) and fission products like Zr, Ru and Eu from 3.5M nitric acid medium with gamma -irradiated dibutyl derivatives of hexanamide (DBHA), octanamide (DBOA) and decanamide (DBDA) in dodecane has been investigated as a function of absorbed dose up to 184 MRads. The results indicate that the K sub d value for extraction of U(VI) decreases gradually, while K sub d for extraction of Pu(IV) decreases rapidly with dose up to 35 MRads, increasing thereafter with dose, indicating synergistic effects of radiolytic products at higher doses. Ruthenium and Eu are not extracted in the entire dose range up to 184 MRads, while extraction of Zr(IV) increases steadily up to 50 MRads and increases rapidly thereafter, indicating synergistic effect of radiolytic products similar to that of Pu(IV) beyond a dose of 50 MRads. The extractabiltiy of U(VI) and Pu(IV) with 1M dibutyl decanamide (DBDA) in dodecane was studied for uranium loading up to 75 mg/ml and Pu loading up to 3 mg/ml. The percent extraction was found to vary from 91-71 for U and 95-89 for Pu, respectively. Quantitative stripping of U can be achieved with 0.01M nitric acid and Pu with 0.5M nitric acid and 0.05M hydroxylamine solution in two steps from an organic phase loaded with 53.2 mg/ml of U.