Mineral–water interactions and their influence on the physical behavior of highly compacted Na bentonite

Na bentonite is the active component of one of the engineered barriers that are being considered in Sweden to surround the final disposal sites of radioactive wastes from nuclear reactors. It has been chosen because of its low permeability and ion diffusivity and of its self-healing ability through swelling. These properties are due to mineral–water interactions that yield a microstructural pattern with very narrow passages and a low average mobility of interparticle water molecules at high bulk densities.