ADSORPTION OF EUROPIUM(III) AND AMERICIUM(III) ON KAOLINITE AND MONTMORILLONITE IN THE PRESENCE OF HUMIC-ACID

Distribution of trace amount of Eu(III), or Am(III), in the aqueous/so lid system containing humic acid and kaolinite, or montmorillonite, wa s studied by batch experiments. Humic acid was also adsorbed on the cl ay minerals and its adsorption isotherm can be regarded as a Langmuir type. it is shown that Eu(III), or Am(III), exists as humate complex e ither in the aqueous or on solid phase in the system including kaolini te, or montmorillonite. These results suggest that the organic-inorgan ic complex like clay minerals coated with humic substances is importan t as metal reservoir in the environment.