Determination of Trace Americium in the Presence of Large Amount of Plutonium by Extraction α Spectrometry

The effect of the acidity in aqueous phase, phase-ratio, times of extraction and concentration of extractant on the extraction of Pu(Ⅳ) and Am(Ⅲ) from nitric acid solution by 1-phenyl-3-methyl-4-benzoylpyrazolone-5(PMBP) in organic solution were studied. The results show that the optimum conditions of Pu and Am separation are summed up as 2 mol/L of nitric acid solution, 1∶1 of phaseproportion, 0.1 mol/L PMBP-dimethylbenzene, a single extraction and a single washing. The separation factor between Pu and Am(SF(Pu/Am)) is about 10⁶. The relative deviation for determination of Am is no more than 8％ when C (Pu)/ C (Am) is no less than 10⁶.