Densification of Ba2NaIO6 ceramic wasteform for enhanced iodine immobilization

IF 3.2 2区工程技术 Q3 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Nuclear Materials Pub Date : 2025-07-28 DOI:10.1016/j.jnucmat.2025.156062

Yi Zhao , Qu Ai , Shi-Kuan Sun , Sheng-Heng Tan , Xiao Liang , Wei-Ming Guo , Hua-tay Lin

{"title":"Densification of Ba2NaIO6 ceramic wasteform for enhanced iodine immobilization","authors":"Yi Zhao , Qu Ai , Shi-Kuan Sun , Sheng-Heng Tan , Xiao Liang , Wei-Ming Guo , Hua-tay Lin","doi":"10.1016/j.jnucmat.2025.156062","DOIUrl":null,"url":null,"abstract":"<div><div>Radioactive iodine-129 (129I) presents a major challenge for nuclear waste management due to its long half-life and high environmental mobility. The design of iodine-bearing wasteforms is expected to balance the iodine loading with the chemical durability. Additionally, the volatile nature of iodine during high-temperature processing necessitates careful selection of wasteform type and accurate control of heat-treatment condition. This study introduces periodate-based Ba2NaIO6 double perovskites as the ceramic wasteform for immobilization of 129I. Ba2NaIO6 powder was initially synthesized by solid state reaction at 650 °C, followed by densification using spark plasma sintering (SPS) at 900–1000 °C under vacuum. It was found that optimal densification was achieved at 950 °C, with a relative density of 97.69 %. Phase-assemblage and microstructural analyses confirmed the thermal stability of Ba2NaIO6 phase, which maintained Fm-3 m double perovskites structure and minimal lattice distortion post-sintering. EDS mapping and composition analysis demonstrated the uniform distribution and effective incorporation of iodine in the matrix. XPS analysis revealed that iodine remained primarily in the +7 oxidation state, indicative of the chemical integrity during sintering. Leaching rate tests further displayed the excellent chemical stability, where the normalized iodine release rate of 1.65 ± 0.16 × 10–4 g/(m2·d) after 7 days was determined. The sintering condition, iodine incorporation capacity, and dissolution rate were systematically compared with previously reported iodine-containing wasteforms.</div></div>","PeriodicalId":373,"journal":{"name":"Journal of Nuclear Materials","volume":"616 ","pages":"Article 156062"},"PeriodicalIF":3.2000,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Nuclear Materials","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022311525004568","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

Radioactive iodine-129 (¹²⁹I) presents a major challenge for nuclear waste management due to its long half-life and high environmental mobility. The design of iodine-bearing wasteforms is expected to balance the iodine loading with the chemical durability. Additionally, the volatile nature of iodine during high-temperature processing necessitates careful selection of wasteform type and accurate control of heat-treatment condition. This study introduces periodate-based Ba₂NaIO₆ double perovskites as the ceramic wasteform for immobilization of ¹²⁹I. Ba₂NaIO₆ powder was initially synthesized by solid state reaction at 650 °C, followed by densification using spark plasma sintering (SPS) at 900–1000 °C under vacuum. It was found that optimal densification was achieved at 950 °C, with a relative density of 97.69 %. Phase-assemblage and microstructural analyses confirmed the thermal stability of Ba₂NaIO₆ phase, which maintained Fm-3 m double perovskites structure and minimal lattice distortion post-sintering. EDS mapping and composition analysis demonstrated the uniform distribution and effective incorporation of iodine in the matrix. XPS analysis revealed that iodine remained primarily in the +7 oxidation state, indicative of the chemical integrity during sintering. Leaching rate tests further displayed the excellent chemical stability, where the normalized iodine release rate of 1.65 ± 0.16 × 10^–⁴ g/(m²·d) after 7 days was determined. The sintering condition, iodine incorporation capacity, and dissolution rate were systematically compared with previously reported iodine-containing wasteforms.

Abstract Image

查看原文本刊更多论文

Ba2NaIO6陶瓷废渣强化碘固定化的致密化研究

放射性碘-129 （129I）由于其长半衰期和高环境流动性，对核废料管理提出了重大挑战。含碘废物的设计是为了平衡碘负荷和化学耐久性。此外，碘在高温处理过程中的挥发性要求仔细选择废物类型和精确控制热处理条件。本研究介绍了高碘酸盐基Ba2NaIO6双钙钛矿作为129I固定化的陶瓷废弃物。采用650℃固相反应合成Ba2NaIO6粉末，900 ~ 1000℃真空放电等离子烧结（SPS）致密化。结果表明，在950℃下致密化效果最佳，相对密度为97.69%。相组合和微观结构分析证实了Ba2NaIO6相的热稳定性，烧结后保持了fm - 3m双钙钛矿结构和最小的晶格畸变。能谱图和成分分析表明，碘在基质中均匀分布，有效掺入。XPS分析显示，碘主要保持在+7氧化态，表明了烧结过程中的化学完整性。浸出率试验进一步显示出优异的化学稳定性，7天后碘的标准化释放率为1.65±0.16 × 10-4 g/（m2·d）。并与已有报道的含碘废水进行了烧结条件、碘掺入量和溶出率的系统比较。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Nuclear Materials 工程技术-材料科学：综合

CiteScore

5.70

自引率

25.80%

发文量

601

审稿时长

63 days

期刊介绍： The Journal of Nuclear Materials publishes high quality papers in materials research for nuclear applications, primarily fission reactors, fusion reactors, and similar environments including radiation areas of charged particle accelerators. Both original research and critical review papers covering experimental, theoretical, and computational aspects of either fundamental or applied nature are welcome. The breadth of the field is such that a wide range of processes and properties in the field of materials science and engineering is of interest to the readership, spanning atom-scale processes, microstructures, thermodynamics, mechanical properties, physical properties, and corrosion, for example. Topics covered by JNM Fission reactor materials, including fuels, cladding, core structures, pressure vessels, coolant interactions with materials, moderator and control components, fission product behavior. Materials aspects of the entire fuel cycle. Materials aspects of the actinides and their compounds. Performance of nuclear waste materials; materials aspects of the immobilization of wastes. Fusion reactor materials, including first walls, blankets, insulators and magnets. Neutron and charged particle radiation effects in materials, including defects, transmutations, microstructures, phase changes and macroscopic properties. Interaction of plasmas, ion beams, electron beams and electromagnetic radiation with materials relevant to nuclear systems.