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Clay Characterisation from Nanoscopic to Microscopic Resolution

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Clay Characterisation from Nanoscopic to Microscopic Resolution Radioactive Waste Management NEA/RWM/CLAYCLUB(2013)1 May 2013 www.oecd-nea.org Clay characterisation from nanoscopic to microscopic resolution NEA CLAY CLUB Workshop Proceedings Karlsruhe, Germany 6-8 September 2011 NEA Unclassified NEA/RWM/CLAYCLUB(2013)1 Organisation de Coopération et de Développement Économiques Organisation for Economic Co-operation and Development 28-May-2013 ___________________________________________________________________________________________ _____________ English - Or. English NUCLEAR ENERGY AGENCY RADIOACTIVE WASTE MANAGEMENT COMMITTEE Unclassified NEA/RWM/CLAYCLUB(2013)1 Cancels & replaces the same document of 24 May 2013 Integration Group for the Safety Case (IGSC) CLAY CHARACTERISATION FROM NANOSCOPIC TO MICROSCOPIC RESOLUTION NEA CLAY CLUB Workshop Proceedings Karlsruhe, Germany 6-8 September 2011 Update of the title of the document on the official OLIS cover page. For any additional information, please contact Mr. Hiroomi AOKI at [email protected]. English JT03340363 Complete document available on OLIS in its original format - This document and any map included herein are without prejudice to the status of or sovereignty over any territory, to the delimitation of Or. English international frontiers and boundaries and to the name of any territory, city or area. NEA/RWM/CLAYCLUB(2013)1 FOREWORD A wide spectrum of argillaceous media are being considered in Nuclear Energy Agency (NEA) mem- ber countries as potential host rocks for the final, safe disposal of radioactive waste, and/or as major constituent of repository systems in which wastes will be emplaced. In this context, the NEA estab- lished the Working Group on the "Characterisation, the Understanding and the Performance of Argil- laceous Rocks as Repository Host Formations" in 1990, informally known as the "Clay Club". The Clay Club examines various argillaceous rocks that are being considered for the underground disposal of radioactive waste, ranging from soft clays to indurated shales. Very generally speaking, these clay rocks are composed of fine-grained minerals showing pore sizes from < 2nm (micropores) up to > 50nm (macropores). The water flow, solute transport and mechanical properties are largely determined by this microstructure, the spatial arrangement of the minerals and the chemical pore water composition. Examples include anion accessible ("geochemical") porosity and macroscopic membrane effects (chemical osmosis, hyperfiltration), geomechanical properties and the characteristics of two-phase flow properties (relevant for gas transport). At the current level of knowl- edge, there is a strong need to improve the nanoscale description of the phenomena observed at a more macroscopic scale. However, based on the scale of individual clay-minerals and pore sizes, for most of the imaging techniques this resolution is a clear challenge. The workshop, hosted by the Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Tech- nology (KIT) in the Akademiehotel Karlsruhe (Germany) from the 6th to the 8th of September 2011, was intended to give, inter alia, a discussion platform on: The current state-of-the-art of different spectro- microscopic methods New developments addressing the above mentioned knowledge gaps in clays. The perception of the interplay between geometry and electrostatics of experimentalists and molecular / Monte Carlo modeling groups providing valuable information on a lattice (1 clay surface; Å-scale). This workshop was spo nsored by t he Federal Ministry of Economy and Technology ( BMWi, G er- many). 3 TABLE OF CONTENTS FOREWORD .......................................................................................................................................... 3 EXPECTATIONS, OPEN QUESTIONS TO BE ADDRESSED IN THE WORKSHOP WITHIN THE CONTEXT OF A DEEP GEOLOGICAL REPOSITORY IN CLAY FORMATIONS ................ 6 Synopsis SESSION –I “Chemical Information under high spatial resolution” ................................ 11 Synopsis SESSION –II “Pore structure and connectivity” ............................................................... 13 Synopsis SESSION III & IV “Water and ion mobility, upscaling and implementation in model approaches” ........................................................................................................................ 14 CONCLUSIONS ................................................................................................................................... 17 APPENDIX A – ABSTRACTS OF PRESENTATION ....................................................................... 18 SESSION –I “Chemical Information under high spatial resolution” ............................................... 18 Glass Corrosion and Secondary Clay Mineral Formation: The Fate of Ni and Ce as Revealed by µ-XRF/XAS Techniques ...................................................................................... 19 3D Chemical Information in Clays Using Synchrotron Techniques ............................................. 27 Application of NanoSIMS on Organo‐Mineral Structures ............................................................ 34 Poster Presentations .......................................................................................................................... 40 A SEM-EDX Study of the Processes at the Concrete/Compacted Bentonite Interface ................ 41 A Method for on-Line Measurements of pH in Compacted Bentonite ......................................... 45 Characterization of Colloids Extracted from Two Synthetic Clay Materials by Flow Field Flow Fractionation (FFFF) Coupled to ICP-MS Detector ..................................... 49 Mineralogical and Microfabric investigation of the Sandy Facies of Opalinus Clay (Mont Terri) ...................................................................................................... 53 X-ray Microspectroscopic Investigations of Ni(II) Uptake by Argillaceous Rocks of the Boda Siltstone Formation IN Hungary .............................................................................. 58 Y(III) Binding to the Smectite Hectorite ....................................................................................... 62 Session –II “Pore structure and connectivity” .................................................................................. 66 BIB-SEM of Representative Area Clay Structures: Insights and Challenges ............................... 67 X-ray Tomography and Impregnation Methods to Analyze Pore Space Hetreogeneities at the Hydrated State ............................................................................................................................... 75 Spatial analysis of tomographic data and its implications on mass transport in Opalinus Clay ... 84 X-ray Micro toMography as a Tool for Studying Localized Damage / Deformation in Clay Rock .................................................................................................................................. 91 4 Poster Presentations ........................................................................................................................ 100 On-Going Bentonite Pore Water Studies by NMR and SAXS ................................................... 101 Homogeneity vs. Heterogeneity of Porosity in Boom Clay ........................................................ 105 Qualitative and Quantitative Characterization of Porosity in a Low Porous and Low Permeable Organic Rich Shale by Combining Broad Ion Beam and Scanning Electron Microscopy (BIB-SEM) ........................................................................ 109 SAXS and TEM Investigation of Bentonite Structure ................................................................ 113 Discriminating between Interlayer Pores and Macropores in Na Montmorillonite .................... 117 Comparing Microstructure and Pore Size Distribution of the Shaly and Sandy Facies in Opalinus Clay (Mont Terri, Switzerland) ................................................................... 121 Session –III & IV “Water and ion mobility, upscaling and implementation in model approaches” ..................................................................................................................... 125 Effects of Organics on the Adsorption and Mobility of Metal Cations in Clay Systems: Computational Molecular Modeling Approach........................................................................... 126 Linking the Diffusion of Water in Compacted Clays at Two Different Time Scales: Tracer Through-Diffusion and QENS ......................................................................................... 134 How is the Current Nano/Microscopic Knowledge Implemented in Model Approaches? ......... 142 Poster Presentations ........................................................................................................................ 147 Interaction of Pu with Opalinus Clay Studied by µ-XRF, µ-XRD, and µ-XANES .................... 148 Microstructural Analysis by X-ray Nano-CT and Its Implications on HDO Diffusion in Compacted Montmorillonite ....................................................................................................... 151 Review of Studies of Clay Minerals as Significant Component of Potential Host Rocks or Engineering Barriers for Radioactive Waste Disposals Performed at Comenius University in Bratislava................................................................................................................................ 155 List
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