Interaction and stabilization of organic radioactive waste in geopolymer

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04207
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22010:Civil engineering material, execution and construction management-related
• Research Institution: Hokkaido University
• Principal Investigator: Elakneswaran Yogarajah 北海道大学, 工学研究院, 准教授 (60769090)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: セメント化学 / ゲオポリマー / 油

Outline of Final Research Achievements

The metakaolin-based geopolymer could not solidify the oil. However, the geopolymer can successfully solidify oil content with the help of a surfactant that changes the surface of the oil from negative to positive, allowing it to interact with the opposing surface of the geopolymer. However, the compressive strength of the resulting composite decreased as the oil content increased due to an increase in porosity, and as the hydration products filled the pores over time, the strength increased. According to the results of TOC analysis, the oil is firmly immobilised within the geopolymer, and after long-term immersion in water, the amount of leaching gradually approaches 0.2%. This is a very small quantity, effectively demonstrating the successful achievement of oil immobilisation using metakaolin-based geopolymer.

Free Research Field

放射性廃棄物

Academic Significance and Societal Importance of the Research Achievements

この研究結果から、地質重合体は油を固める有望な解決策となり得ることが示唆される。ただし、油の存在によって引き起こされる多孔質には十分な注意が払われる必要があり、その結果得られる複合材料が、意図された用途に十分な強度を持つことを確認する必要がある。さらに、硬化時間、混合比、環境条件などの要因を考慮して、地質重合体と油の複合材料を最適化するために追加の研究が必要である。これにより、実用的な応用における効果と耐久性を最大化することができる。