NEPTUNIUM OXALATE PRECIPITATION FROM THE SIMULATED RADIOACTIVE LIQUIDWASTE

The partitioning of Np and Nd by precipitation with oxalic acid and as corbic acid was investigated in the simulated radioactive liquid waste , which was composed of 10 elements of alkali, alkaline earth and tran sition metals in nitric acid solution. The effect of concentrations of ascorbic acid and nitric acid on the precipitation yield and the puri ty of Nd and Np in the simulated radwaste was examined at 0.5M oxalic acid. As a result, Np was coprecipitated with Nd as a carrier and its precipitation yield was increased with ascorbic acid and nitric acid c oncentrations. It was also found that the initial concentrations' of 0 .25 M ascorbic acid, 2 M nitric acid and 0.5 M oxalic acid were desira ble as an optimum condition for oxalate precipitation of Np and Nd fro m the simulated radwaste if Pd could be removed in the simulated radwa ste prior to oxalate precipitation. Precipitation yield of Pd increase d with increasing ascorbic acid. This is due to the reduction of Pd+2 into Pd metal by ascorbic acid.