Presentation Information
[1B09]Aggregation and Dissolution Mechanisms of ZnO Nanoparticles from Nuclear Fuel Debris
*Yiwei Zhang1, Nicholas Kai John Yamanaka1, Naokazu Idota1, Takehiko Tsukahara1 (1. Science Tokyo)
Keywords:
zinc oxide nanoparticle,aggregation kinetics,dissolution,decommissioning
Nanoparticles generated from the FDNPP decommissioning undergo complex physicochemical transformations that affect their fates in the environment. This study investigates the aggregation and dissolution behaviours of ZnO nanoparticles (NPs), which is selected as a representative engineering material derived from structural paint in the PCVs and widely used in industry. To simulate the practical conditions, ZnO NPs were exposed to hydrogen peroxide solutions ranging from 3×10-5 M to 3 M. The results show that ZnO NPs aggregation is strongly dependent on the H2O2 concentrations. At low H2O2 concentrations, suspensions remain initially stable but eventually aggregate due to the release of Zn2+, with kinetics consistent with Smoluchowski model. In contrast, high H2O2 concentrations induce rapid aggregation followed by partial disaggregation of large clusters. These findings provide critical understanding of nanoparticle denaturation and their effects on decommissioning.