【摘要】 建立了离子交换法与沉淀法相结合的、从高放废液中分离79Se的放化流程。该流程具有去污效果好的特点,对137Cs,90Sr,90Y,99Tc,154Eu的去污因子大于104,对125Sb,113Sn的去污因子大于103,对237Np为2×102。整个流程的收率约为53%。由该流程分离出的79Se样品能够很好地满足液闪测量和质谱测量的要求。更多还原

【Abstract】 A radiochemical procedure for separation of ⁷⁹Se from HLLW based on ion-exchange chromatography and precipitation is developed. The HLLW sample is first loaded to an anion exchange（column） and then eluted with 8 mol/L HCl.The effluent is transferred to 0.75 mol/L HNO₃ medium,and then let it pass a mixed ion exchange column and eluted with 0.3 mol/L HNO₃. After addition of Na₂SeO₃ carrier and holdback carriers for ¹³⁷Cs,⁹⁰Sr,¹²⁵Sb,etc.,the ⁷⁹Se is precipitated with Na₂SO₃ as elemental Se from the effluent.After washing,the Se precipitate is dissolved in nitric acid.Aliquots of the final solution are measured by HP Ge gamma spectrometry,liquid scintillation spectrometry and ICP-MS.The decontamination factors for interfering radionuclides are estimated.The final recovered ⁷⁹Se is roved to be raiochemically pure.The overall recovery for ⁷⁹Se is about 53%.更多还原