Ethylenediaminetetraacetic acid (EDTA)를 이용한 인산석고 야적장 침출수 중의 $^{226}Ra$ 분석법 개발
김근호;김용재;장병욱;
Determination of $^{226}Ra$ Isotope in the Leachate around Phosphogypsum Stack Using Ethylenediaminetetraacetic Acid (EDTA)
Kim, Geun-Ho;Kim, Yong-Jae;Chang, Byung-Uck;
ABSTRACT
Ba is the most useful element to get the $Ba(Ra)SO_4$ precipitate. However, when the high concentrations of ions such as sulfate, calcium are existed in the leachate of phosphogypsum stack, it is difficult to get the $Ba(Ra)SO_4$ precipitate. Since this reason, the developed method for the Ba coprecipitate using EDTA was performed to determine the $^{226}Ra$ concentration in the high sulfate sample. The average concentration of $^{226}Ra$ in a leachate of phosphogypsum using this method was 0.102 $Bq{cdot}kg^{-1}$ and the minimal detectable activity is 3.4 $mBq{cdot}kg^{-1}$. The $mBq{cdot}kg^{-1}$ method was 0.102 $Bq{cdot}kg^{-1}$ and the minimal detectable activity is 3.4 $mBq{cdot}kg^{-1}$. The $^{226}Ra$ stock solution and the CRM (Certified Reference Material) were analyzed to verify this method. In analyzed $^{226}Ra$ stock solution, bias with added concentration was approximately 1% and the correlation curve between $^{226}Ra$ concentration in simulated standard sample and measured $^{226}Ra$ concentration showed good agreement with a correlation coefficient ($R^2$) of 0.99. In analyzed CRM, maximum bias with reference value was 5.8% (k=1) and the analytical results were in good agreement with the reference value.