PMBP萃取α能谱法测定大量钚中微量镅

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

摘要: 研究了1-苯基-3-甲基-4-苯甲酰基吡唑酮-5（PMBP）萃取HNO₃溶液中镅、钚的性能,研究了水相酸度、相比（有机相∶水相）、萃取次数、萃取剂浓度等对PMBP萃取性能的影响。实验结果表明，在酸度为2 mol/L、相比为1∶1时，0.1 mol/L PMBP-二甲苯对分析样品进行一次萃取一次洗涤即能有效的分离大量钚，满足α能谱对微量镅的测定。该方法钚与镅的分离系数约为10⁶，在C（Pu）/C（Am）≥10⁶时对Am的相对偏差不大于8％。

Abstract: 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.