Extraction behaviour of Pu(IV), U(VI) and some fission products with gamma irradiated dihexyl- and methylbutyl- substituted dialkylamides

The extraction of Pu(IV), U(VI), Zr(IV), Eu(III) and ruthenium with gamma irradiated dihexyl-derivatives of hexanamide (DHHA), octanamide (DHOA) and decanamide (DHDA) and methylbutyl-derivatives of hexanamide (MBHA), octanamide (MBOA) and decanamide (MBDA) in dodecane from 3.5M HNO3 has been studied as a function of dose up to 184 M rads. The results indicate that the Kd values for extraction of U(VI) decrease gradually up to 50 M rads and becomes almost constant thereafter while ruthenium and europium are not extracted in the entire dose range. Plutonium (IV) extraction decreases up to a dose of 20 M rads (for DHHA, DHOA and DHDA) and 30 M rads (for MBHA and MBDA) and increases rapidly thereafter up to a dose of 72 M rads indicating synergistic effects of radiolytic products at higher doses. The radiolytic degradation of amides was measured by quantitative infrared spectroscopy and was found to follow the order DHHA > DHOA > DHDA > MBOA > MBDA > MBHA at 184 M rads having the amines and carboxylic acids as the main radiolytic products. Extraction of Zr(IV) increases gradually up to a dose of 72 M rads. The fall in Kd values after 72 M rads is due to third phase formation. (author). 8 refs., 2 figs