The sorption of Eu(III) on Opalinus Clay at elevated temperatures and in presence of organics

Presently, argillaceous rock formations are under investigation as potential host rocks for nuclear waste repositories. In addition to diffusion the sorption of radionuclides on mineral phases is an important physicochemical process. Concerning the required long-term safety and risk assessment of the storage of high level radioactive waste the understanding of these processes is essential. Opalinus Clay (OPA) is a complex argillaceous rock with illite, chlorite, kaolinite, quartz, calcite, pyrite and siderite as main components and a very low content of natural organic matter (small organic molecules, humic acids). This natural occurring clay rock is discussed as host rock formation for nuclear waste repositories. (orig.)