| 초록 |
Understanding of the long-term geochemical behavior of various forms of radionuclides including colloidal nanoparticles is required for the reliable safety assessment of deep geological repository systems of spent nuclear fuels. In this study, the colloidal behavior of tetravalent uranium nanoparticles (U(IV)NPs) was investigated under reducing aqueous conditions by varying the ionic strength, pH and concentrations of anions and an organic ligand, which are among the key parameters that define a groundwater system. First, the effect of ionic strength and anions on the formation and stability of U(IV)NPs colloids was studied. Based on DLS analysis, Cl- more significantly affects the colloidal stability of U(IV)NPs than ClO4-. Second, the effects of pH and organic ligand (nitrocatechol, nCA) on colloid stability of U(IV)NPs were also investigated. Interestingly, our results demonstrate that the surface adsorption of nCA at high pH was found to improve the stability of U(IV)NPs. |
