Assessment of 137Cs decontamination of concrete by the reagent method

The particulars of radioactive contamination of concrete wastes by Cs-137 were studied. x-Ray phase analysis and chemical analysis show that clayey materials, including Al2O3, Fe2O3, K2O, and MgO, on which Cs-137 sorption is possible, were present in the concrete wastes. The content and form in which Cs-137 was found in radioactive concrete wastes from nuclear power facilities as well as in model samples were determined. When the wastes were treated with nitric acid the binder dissolved and a polydisperse suspension formed. The suspension consisted of three phases: solution, fine suspension, and rapidly settling precipitate of heavy filler particles. x-Ray phase analysis was performed and the Cs-137 mass ratio and distribution in the phases were determined. The possibility of decontaminating the concrete by a reagent method was evaluated.