Abstract
The bentonite has a variety of industrial applications. It is used as a stabilizing and suspending agent, an adsorbent and clarifying agent, a buffer material for barriers in geological disposal facilities for radioactive waste, liners for remediation of contaminated soils and ponds.
Characterization of the morphological changes of the bentonite during the process of swelling and shrinkage is very important for these applications [1-3]. The environmental scanning electron microscope (ESEM) allows observation under the water vapour pressure from units to thousands of Pa and at a selected temperature from -20 ° C to 1500 ° C.
Moreover, these samples do not have to be treated, namely dried and covered with the conductive metal layer [1, 4]. ESEM is also very effective for in-situ investigation of bentonites, which can be realised under dynamically changing relative humidity (RH).