Selective ion exchangers for the purification of the radioactive waste liquids

Laboratory of Radiochemistry, University of Helsinki, has together with IVO Power Engineering , Finland, developed two ion exchange materials, CsTreat and SrTreat, which are being manufactured and marketed by Selion Oy, Finland. CsTreat is an extremely selective transition metal hexacyanoferrate exchanger for the removal of radioactive cesium from nuclear waste solutions. It has been successfully used at nuclear power plants, in Finland and USA, for the removal of cesium from both dilute and concentrated salt solutions. SrTreat is a titanate product and it is very effective for strontium. Both materials have been recently used at Japan Atomic Energy Research Institute in a purification process for reprocessing waste effluents. In addition to performances of these two materials the paper discusses general problems met with in radionuclide removal processes at nuclear plants and gives a board overview of new developments of ion exchange materials. (author)