Sorption nuclides on organic colloids and their migration through porous media (II)

Nagasaki, Shinya*

Model V and NICA-Donnan model, which can describe the interaction of humic acids with metals, were reviewed and CD-MUSIC model, which is a typical surface complexation model of metals with solid surfaces, was also introduced. In Model V, the equilibrium of chemicals among water in environment, sediments and solids is considered. In NICA-Donnan model, the electrostatic interactions due to the difference in the activities between humic acids and bulk is included and the heterogeneity of binding sites in humic acids is also taken into account. In this report, the problems of these models was summarized and the future development was discussed. In experimental part, the proton dissociation reaction and the interaction with Cu were investigated, by titration experiments using Aldrich humic acids. Considering NICA-Donnan model, the interaction parameters of the proton dissociation reaction and the interaction with Cu were evaluated. In calculation part, the mixing characteristics of water flow in fracture junctions was discussed by Real-coded Lattice Gas model. The mixing ratio at the outlet of fracture junctions was analyzed qualitatively and quantitatively as a function of Peclet number. Furthermore, the trajectory of colloid transport in the laminar flow at bending tube was calculated, and the effect of the mass of colloid was qualitatively studied. The random walk and diffusion phenomena of colloids were found to be successfully calculated by Real-coded Lattice Gas model developed in this work.