Study on Monitoring of ⁹⁰Sr in Aqueous Solution Using SuperLig®620

In order to achieve continuous monitoring of ⁹⁰Sr in aqueous solution, ⁹⁰Sr was firstly separated selectively and enriched by SuperLig®620 solid phase extraction beads, which was then measured in-situ using plastic scintillator. The influences of ⁹⁰Sr activity on two-phase equilibrium were studied and the results show that the concentration in aqueous solution is directly proportional to that captured on the column in 0.2 mg/L Sr-0.01 mol/L HNO₃ medium. So the concentration of ⁹⁰Sr in aqueous solution can be analyzed by detecting ⁹⁰Sr on the column. The detection efficiency and minimum detectable activity are 21.3% and 2.6 Bq/L, respectively. The concentration of ⁹⁰Sr in low level radioactive waste water was analyzed using the above method and the analytical error is lower than 20%.