Solvent Extraction of Uranium with N,N-Di(2-Ethylhexyl)Octanamide from Nitric Acid Medium

Solvent extraction of uranium from a nitric acid medium was performed with N,N-di(2-ethylhexyl)octanamide (DEHOA) by a single-stage batch method, and the distribution ratio equation of U(VI) was derived as, where [NO3](aq) and [DEHOA(Free)](U) represented the concentration of nitrate ion in the aqueous phase and free DEHOA concentration in the organic phase, respectively. Furthermore, the nitric acid distribution was also evaluated in the initial nitric acid range of 0.317.2mol/dm(3) (M), and the distribution ratio equation was obtained as, where [H+](aq) and [DEHOA(Free)](H) represented the acid concentration in the aqueous phase and free DEHOA concentration in the organic phase, respectively. Batch experiments to evaluate the time dependence of U(VI) extraction and the U(VI) loading capacity of DEHOA were also performed. It was revealed that U(VI) extraction by DEHOA reached an equilibrium state within a few minutes, and the loading capacity was 0.71M when the concentrations of DEHOA and nitric acid were 1.5 and 3.0M, respectively.