Sorption and desorption of radioiodine and radioselenium on calcareous soil and its solid components

This paper is an extension of previous papers^1–3. The breakthrough curves and the displacement curves of¹²⁵I⁻ and⁷⁵SeO₃ on the calcareous soil, the treated soil to remove CaCO₃ and the treated soil to remove organic matter were determined at pH 7.8, at 20°C and in the presence of 1·10⁻³ or 1·10⁻⁴ mol/l CaCl₂. These results from column experiments and from batch experiments in the previous papers^1,2 were mutually complementary. It can be definitely concluded that iodide is retained to a very small degree and tetravalent-selenium is retained to a small degree by calcareous soil and that organic matter in calcareous soil acts as a significant trap of iodide and CaCO₃ acts as a trap of tetravalent selenium. Iodide and tetravalent-selenium would be expected to have relatively high dissemination in calcareous soil.