Evaluation of Radioactive Strontium Distribution Coefficient by Analyzing Background Stable Strontium.

A new method of evaluating the distribution coefficient (Kd ) of radioactive Sr was examined. The method is based on the measurement of the solid-liquid concentration distribution ratio (Rd ) of background stable Sr. To verify the method, the Kd 's of both the radioactive Sr and stable Sr were simultaneously measured by batch sorption experiments in which radioactive Sr with a constant concentration and stable Sr with various concentrations coexisted. The Rd of background stable Sr was then measured by extraction with 0.1N CH3COONH4 and 0.1N HCl solutions to compare Rd with Kd. The results showed that the Kd 's of radioactive Sr agreed with those of stable Sr, and that the Rd corresponded to the Kd when the liquid-phase concentration of stable Sr approached the background level. This indicates that the new method of evaluating Kd by using Rd is applicable to Sr.