Diffusion of Ni in Compacted Sodium Bentonite

Vapour transfer in unsaturated compacted bentonite

Results of an experimental and theoretical investigation of heat and moisture movement in unsaturated MX-80 bentonite are presented. A thermo-hydraulic cell that allows measurement of transient temperatures and facilitates the determination of pseudo-transients of moisture content, dry density and chemical composition has been used to perform thermal gradient tests. Results of a number of tests...

An integrated sorption-diffusion model for the calculation of consistent distribution and diffusion coefficients in compacted bentonite.

A thermodynamic sorption model and a diffusion model based on electric double layer (EDL) theory are integrated to yield a surface chemical model that treats porewater chemistry, surface reactions, and the influence of charged pore walls on diffusing ions in a consistent fashion. The relative contribution of Stern and diffuse layer to the compensation of the permanent surface charge represents ...

Porewater chemistry in compacted re-saturated MX-80 bentonite.

Bentonites of various types are being investigated in many countries as backfill materials in high-level radioactive waste disposal concepts. Being able to understand the chemistry of the porewater in compacted bentonite is very important since it is critical to predicting radionuclide solubilities and to the synthesis of sorption data bases, and hence to repository safety studies. In this pape...

Free porosity investigation of compacted bentonite using XRD

Many countries intend to use compacted bentonite as a barrier in their deep geological repositories for nuclear waste. In order to describe and predict hydraulic conductivity or radionuclide transport through the bentonite barrier, fundamental understanding of the microstructure of compacted bentonite is needed. This study examined the interlayer swelling and overall microstructure of Wyoming B...

Diffusion Mechanism of Sodium Ions in Compacted Montmorillonite under Different NaCl Concentration