title: A modified version of the combined in-diffusion/abrasive peeling technique for measuring diffusion of strongly sorbing radionuclides in argillaceous rocks: a test study on the diffusion of caesium in Opalinus Clay.
abstract: A filter free diffusion set-up was developed for measuring the diffusion of strongly sorbing radionuclides in indurated argillaceous rocks such as Opalinus Clay (OPA) that normally disintegrate when contacted with a solution. Small bore cores drilled parallel to the bedding plane and embedded in epoxy resin were found to be stable and could be used for performing in-diffusion measurements. The method was tested with the diffusion of caesium, spiked with caesium-134, in Opalinus Clay. The profile of Cs in the clay sample was determined with a modified version of the abrasive peeling technique. The diffusion parameters obtained for caesium were in fair agreement with those determined earlier using the classical through-diffusion technique where stainless steel filters were used to confine the samples.
authors.affiliation: Paul Scherrer Institute, ViIligen, Switzerland. Electronic address: luc.vanloon@psi.ch.
authors.forename: Luc R
authors.initials: LR
authors.lastname: Van Loon
authors.affiliation: Paul Scherrer Institute, ViIligen, Switzerland.
authors.forename: Werner
authors.initials: W
authors.lastname: Müller
keywords: Abrasive peeling; Argillaceous rocks; Caesium; In-diffusion; Opalinus Clay