Extraction of uranium (VI) and thorium (IV) from nitric acid with N,N-dibutyloctanamide

N,N-dibutyloctanamide (DBOA) was synthesized, The extraction of HNO3 with DBOA was studied and the extracted species, HNO3. DBOA was suggested. The value of extraction equilibrium constant was calculated to be 0.20 mol(-2).L-2, Extraction of U(VI) from nitric acid solutions with DBOA in toluene has also investigated. The stoichiometry of extracted species, UO2(NO3)(2).(DBOA)(2), was established and the, extraction constant was derived to be 4.93 mol(-4).L-4. The structure of extracted complex was discussed by the aid of IR spectra. The value of the change in extraction enthalpy was calculated. The experimental results indicate that DBOA can extract UO22+ efficiently from nitric acid solutions but Th4+ and Fe3+ poorly. Therefor DBOA gives a high separation factor between uranium and thorium, which shows that this extractant is promising in the U-Th fuel reprocessing.