[2G08-12] Stabilization and Immobilization 1

[2G08] A study of the compaction properties of potassium and metakaolin-based geopolymers for radioactive metals.

*Yaru Yang¹, Hisayuki Suematsu¹, Thi Mai Dung Do², Thi Chau Duyen Le⁴, Tadachika Nakayama¹, Koichi Niihara¹, Gordon Thorogood³ (1. Extreme Energy-Density Research Institute, Nagaoka University of Technology , 2. Department of Nuclear System Safety Engineering, Nagaoka University of Technology, 3. ANSTO, New Illawarra Rd, Lucas Heights, NSW, 2234, Australia , 4. Dandang University of Science and Technology,54 Nguyen Luong Bang, Lien Chieu, Danang City, Vietnam)

Keywords:geopolymer, metakaolin, ion- exchange, compaction, leaching

Geopolymers are inorganic polymers composed of AlO₄ and SiO₄ tetrahedral structural units and a three-dimensional network structure. In the decommissioning of JMTR, the geopolymer compaction method for radioactive Al wastes has been considered. For this purpose, the stability of geopolymer after compact the radioactive Al metal ions is important. In this study, geopolymers were made of EFACO silica, metakaolin powder, potassium hydroxide and potassium silicate solution with molar ratios of Al: Si: K: H₂O =1: 2.1: 0.8: 8. Al powder and Al wire will added in the samples. Then the samples were cured 60 degree for 1 day and then kept at RT until the 14 days. After 2 weeks curing, geopolymer samples were leaching in water for ( 2h, 7h, 24h, 48h, 72h ). The result showed that sample added with Al powder appeared more cracks than added with Al wire. ICP-MS will be use for detacting the Al ions in the liquied.