[2B09-13] Deburis 2

3:15 PM - 3:30 PM JST(6:15 AM - 6:30 AM UTC)

[2B11] Studies on Nanoparticles Aggregation and Dissolution Mechanisms from Nuclear Fuel Debris

*Yiwei Zhang¹, Nicholas Kai John Yamanaka¹, Cong Chao², Miguel Pineda², Naokazu Idota¹, Eric S Fraga², Panagiota Angeli², Takehiko Tsukahara¹ (1. Science Tokyo, 2. UCL)

Keywords:

nanoparticle,aggregation,dissolution,nuclear fuel debris,decommissioning

This study aims to investigate nanoparticle behaviours generated during the Fukushima Daiichi Nuclear Power Plant decommissioning, including their aggregation and dissolution characteristics. Experiments are conducted in both batch and microchannels to demonstrate the distinct behaviours of nanoparticles (CeO₂, ZrO₂, TiO₂ and ZnO nanoparticles) in specific solvents. Hydrogen peroxide (H₂O₂) and nitric acid (HNO₃) are selected to simulate the practical conditions and serve as strong dissolving agents, respectively. The results indicate that CeO₂ and ZrO₂ nanoparticles undergo rapid initial aggregation, followed by slower aggregation kinetics with minimal dissolution. In contrast, ZnO nanoparticles exhibit rapid dissolution without obvious aggregation. These phenomena are partially attributed to variations in electrostatic charges and differences in interfacial reactions. This study provides significant understanding of nanoparticle denaturation and their negative effects on nuclear fuel debris.