A study on the separation of neodymium from the simulated solution of U3Si/Al spent nuclear fuel

The separation of Nd from the simulated U3Si/Al spent fuel solution with sequential two-step anion exchange separation has been studied. To prepare the simulated U3Si/Al spent nuclear fuel, unirradiated U3Si/Al whose composition consists of small U3Si particle dispersed in an Al matrix with Al cladding was dissolved with a mixture of 4 M HCl and 10 M HNO3 and 8 or 15 fission product elements were added to the dissolved solution. The trace amount of silica in the solutions was removed by evaporating to dryness with HF and U was adsorbed on the first anion exchange resin. Neodymium can be purely isolated from the fission product elements with a methanol-nitric acid eluent using the second anion exchange resin. A large excess of Al didn't influence on the elution velocity of Nd, but reduced the eluted contents of Nd, Al, Eu, Gd, Sm and Sr. A large amount of Al was removed first from the column with 3 mL of loading solution (0.8 M HNO3/99.8% MeOH) before Nd elution by the eluent (0.04 M HNO3-99.8% MeOH (1:9)). The recovery of Nd was more than 94%, regardless of Al contents. Taking the 9 to 13 mL fraction of eluate was effective to purely isolate Nd. (author)