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

Abstract

This paper is an extension of previous papers1–3. 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 papers1,2 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.