Characterization and radionuclide retention properties of heat-treated concrete

• Characterization of Fukushima relevant heat-treated concrete.
• Fission product interactions experiments with heat treated concrete.
• Quantification of europium, cobalt and caesium retention.

This study was performed to obtain insight into the characteristics of contaminated cementitious materials which may result from a light water reactor core melt down accident. Such material arose in a huge amount from the Fukushima disaster. We analyzed the elemental and mineralogical composition of similar, heat-treated material and investigated its radionuclide retention properties.We present the radionuclide retention properties of concrete samples which originally were part of an experiment using a thick-walled concrete recipient that had been heated by simulating a reactor melt down. Batch sorption experiments have been performed with the elements Cs(I), Co(II), and Eu(III) in seawater under aerobic conditions. Sorption coefficients were measured: Rs(Eu) ∼5800 ml g−1 and Rs(Co) ∼110 ml g−1. A tentative value for Cs was determined, adulterated by the relatively high release of Cs from the concrete itself.