Silver tungstate-tellurite glass for radioactive iodine immobilization

The use of 235U as a fuel in nuclear power plants results in the formation of various fission products. Among them, 129I exhibits a long half-life (t1/2 = 15.7 million years) and tends to easily volatilize, making its capture and treatment necessary. In this study, silver tungstate-tellurite glass (Ag2O center dot WO3 center dot TeO2 with different mol% of AgI loading) was developed for radioactive iodine immobilization. The glass matrix was investigated by varying the fraction of Ag2O and/or WO3. AgI was added to each matrix, ranging from 0 to 40 mol% in increments of 10 mol %. The glass samples were prepared by the melt-quenching process at 850 degrees C for 90 min. X-ray fluorescence analysis indicated no significant loss of elements in the samples, whose amorphous phase was confirmed by X-ray diffraction analysis. The effects of increasing the amount of AgI on the glass matrix are discussed considering the results of X-ray photoelectron spectroscopy. The leaching properties of all samples were evaluated via the product consistency test-A. Finally, the normalized release of all elements satisfied the US regulation of 2 g/m2.

Automated summary

In this study, silver tungstate-tellurite glass with different loading of AgI was developed for immobilization of radioactive iodine. The effects of increasing the amount of AgI on the glass matrix were investigated. The leaching properties of all samples were evaluated, and it was found that the release of all elements satisfied the US regulation.