The deliquescence and disposal stability of cement waste form containing Na compound

• Published in: Journal of radioanalytical and nuclear chemistry Vol. 331; no. 1; pp. 289 - 295
• Main Authors: Shon, Jong-Sik, Jeon, Hongrae, Kim, Gi-Yong, Lee, Hyun-Kyu, Kim, Tack-Jin
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.01.2022; Springer; Springer Nature B.V
• Subjects: Acceptance criteria; Cement; Chemical composition; Chemistry; Chemistry and Materials Science; Decontamination; Diagnostic Radiology; Hadrons; Hazardous waste management industry; Heavy Ions; Hygroscopicity; Inorganic Chemistry; Leaching; Liquid wastes; Nitric acid; Nuclear Chemistry; Nuclear energy; Nuclear Physics; Physical Chemistry; Radioactive waste disposal; Radioactive wastes; Relative humidity; Solidification; Stability analysis; Waste management; Final disposal; Deliquescence; Acceptance criteria; Na compound; Cementation
• ISSN: 0236-5731; 1588-2780
• DOI: 10.1007/s10967-021-08063-6

According to the waste acceptance criteria of radioactive waste disposal sites, Na or Na compounds cannot be disposed of as they are. Owing to deliquescence, these compounds must be disposed of after being treated into a physicochemically stable form and solidification is the representative stabilization treatment method for such compounds. Na compounds are mostly generated in isotope production processes, such as Fission 99 Mo Production Process (FMPP), or while the nitric acid (HNO 3 ) liquid waste used in various melting and decontamination processes is neutralized into NaOH. The purpose of this study is to assess the disposal stability and the leaching characteristics of Na for the cement waste form containing Na compounds. For this purpose, cement waste forms were fabricated depending on the NaNO 3 contents. In addition, the chemical composition of the Na compounds recovered by drying the liquid waste of FMPP was analyzed, and their deliquescence was examined according to the relative humidity and temperature. Finally, the leaching characteristics of Na for the cement waste form of the FMPP liquid waste were also assessed.