Retention of some hazardous radionuclides from nitric acid solution using tin(IV) antimonate as a cation exchanger

Abstract

The removal of some hazardous radioactive nuclides such as Cs⁺, Co²⁺, Sr²⁺ and/or Eu³⁺ from radioactive liquid waste was carried out either by chemical in-situ precipitation or by using a preformed precipitate of tin(IV) antimonate (SnSb). Stability of the product material for the chemical reagents was investigated at various concentrations of nitric and hydrochloric acids. Capacity and selectivity patterns for Cs⁺, Co²⁺, Sr²⁺ and Eu³⁺ were determined on these matrices. Conditioning of the exhausted tin(IV) antimonate in cement matrix was carried out with the study of some important parameters affecting the properties of the solidified waste forms such as, the compressive strength and the leaching coefficient of these nuclides from the solidified waste form. The leaching coefficient of radioactive nuclides precipitated in-situ with SnSb are smaller than those adsorbed on SnSb or plain ordinary portland cement.