Curing time effect on the fraction of Cs-137 from cement-ion exchange resins-bentonite clay composition

Abstract

To assess the safety of disposal of radioactive waste material in cement, curing conditions and time of leaching radionuclides Cs-137 have been studied. Leaching tests in cement-ion exchange resins-bentonite matrix were carried out in accordance with a method recommended by IAEA. Curing conditions and curing time prior to commencing the leaching test are critically important in leach studies because the extent of hydration of the cement materials determines how much hydration product develops and whether it is available to block the pore network, therepy reducing leaching. Incremental leaching rates R-n (cm/d) of Cs-137 from cement-ion exchange resins-bentonite matrix after 180 days were measured. The results presented in this paper are examples of results obtained in a 20 yr concrete testing project that will influence the design of the engineer trenches system for future central Serbian radioactive waste storing centers.