JUM@P '11: Joint Users' Meeting at PSI 2011

Interaction of Pu with Opalinus Clay studied by µ-XRF, µ-XRD, and µ-XANES

16 Sept 2011, 13:23

2m

WSLA - Foyer (Paul Scherrer Institut, Villigen, Switzerland)

Board: 94

Poster Poster Session II (Friday) Poster session II and lunch

Speakers

Mr Daniel Fröhlich (Johannes Gutenberg University Mainz)Dr Daniel Grolimund (PSI)Mr Jakob Drebert (Johannes Gutenberg University Mainz)Dr Samer Amayri (Johannes Gutenberg University Mainz)Prof. Tobias Reich (Johannes Gutenberg University Mainz)Mr Ugras Kaplan (Johannes Gutenberg Universität Mainz)

Description

Plutonium will be a major contributor to the radiotoxicity of high-level nuclear waste after a storage time of more than 1,000 years due to the long half-lives of Pu-239, Pu-240, and Pu-242. Argillaceous rocks are under consideration as potential host rock formation for the construction of high-level nuclear waste repositories by several European countries, i.e., Belgium, France, Germany, and Switzerland. The interaction of Pu-242 with Opalinus Clay (OPA) from Mont Terri, Switzerland, was studied on a microscopic scale at the SLS MicroXAS beamline. The elemental distributions of Pu, Ca, Fe, and Mn on two OPA thin sections that were contacted with Pu(VI) solutions for 72 h and in an intact OPA bore core in which Pu was diffused over a period of one month were measured by µ-XRF. All samples contained Pu “hot spots” that were investigated by Pu LIII-edge µ-XANES and µ-XRD. As an important result, we found that the highly soluble Pu(VI) was retained by OPA in the reduced and less mobile tetravalent oxidation state of Pu.

Please specify poster or talk

poster

Please specify the session

first day