Study On Radioactive Iodine Curing Glass Material System And Curing Process

With the development of nuclear energy,the disposal of radioactive waste has gradually become a problem that cannot be ignored.Radioactive waste contains about 1%of radioactive iodine.These radioactive iodine elements are easily enriched in the human body and cause cancer.They must be properly disposed of to prevent them from entering nature.Since the properties of iodine are different from uranium and thorium,the current radioactive waste treatment methods are not suitable for the radioactive io-dine.In order to meet the curing requirements of radioactive iodine,several glass ma-terials suitable for curing iodine were studied.A variety of alternative solidified materials were prepared in this paper for the curing of radioactive iodine.The anti-leaching performance was tested in a relatively simple way.The leaching resistance of AgI-Ag2O-P2O5,AgI-Ag2O-Bi2O3-TeO2,Agl-Bi2O3-P2O5,AgI-Ag2O-WO3 glass materials prepared in the study was tested,and the test results were selected as the main evaluation basis..In the experimental results,AgI-Ag2O-WO3 had the best curing effect on iodine,and the leaching amount of iodine in the corresponding leachate was less than 0.05mg/L.In combination with other factors,the AgI-Ag2O-WO3 glass system is preferably used as a solidified body in various cur-ing bodies to be intensively studied and tested.The preparation process of the AgI-Ag2O-WO3 glass system was simply optimized.Comprehensive heat treatment time,heat treatment temperature,melting effect and ef-ficiency and reducing the loss of iodine,the general heat treatment procedure for Agl-Ag2O-WO3 glass is set to 10?/min,the temperature rise end is 650?,holding time is 30min.The iodine loss rate during the thermal processing of AgI-Ag2O-WO3 glass by this process is about 0.3%to 0.4%,and the prepared glass density ranges from 6.55 g/cm3 to 6.82g/cm3.The anti-leaching performance of AgI-Ag2O-WO3 cured glass was tested by the internationally widely used The Product Consistency Test(PCT test)method.The nor-malized leaching rate NRi of element I in the test results is about 1×10-6g/(m2·d).The test results show that AgI-Ag2O-WO3 glass has good fixing effect and leaching re-sistance for element I therein.The surface morphology of AgI-Ag2O-WO3 glass was analyzed by SEM and EDS.All formed AgI-Ag2O-WO3 glass bodies are uniform and smooth and transparent,with only a small number of areas producing minor defects for different reasons.The X-ray diffraction(XRD)test results showed that there was no crystallization in the AgI-Ag2O-WO3 glass prepared in the experiment.The X-ray photoelectron spec-troscopy(XPS)test showed that I in the AgI-Ag2O-WO3 glass exists in the form of I-ion,and W exists in the form of WO42-ion,Ag exists in the form of Ag+ions.The results of the infrared spectroscopy test further prove the judgment of the XPS test on the form of the element.