Interactions of radionuclides in solution with ions and with trace concentrations of solid phase

Abstract

Abstract Interactions of radionuclides in extremely low concentrations were determined by measurement of their apparent self-diffusion coefficients. Formation of trace amounts of hydrolysis products, hydroxides of RuIV, MnIV, FeIII, EuIII and of ionic precipitate of AgI were determined from apparent self-diffusion coefficients. Transition of 85Sr2+ by ion exchange or by coprecipitation into trace amounts of FeIII-hydroxide and MnIV-hydrated oxide was revealed by this method. 85Sr2+ sorbed on trace amounts of FeIII-hydroxide and MnIV-hydrated oxides lost its individual chemical properties. This can negatively affect its separation from solution. Formation of unstable embryos of Ag131I trace precipitate in unsaturated solution at concentration of Ag+ 1 · 10−9 mol · l−1 and 131I−1 · 10−8 mol · l−1 was detected by self-diffusion. Formation of trace amounts of Ag131I led to the decrease of sorption of 131I− on hydrated ferric oxide.