Analysis of thermally stimulated depolarization currents (TSDC) measured on exchanged clays

This work: shows that hydration of clays can be studied by means of a new i nterpretation of thermally stimulated depolarization currents technique. Th ese measurements have been performed on four exchanged natural clays: Na-mo ntmorillonite, Camontmorillonite, kaolinite, and illite, The results are an alyzed using both the recently developed analysis of relaxation times distr ibution and the electronegativity equalization method. They provide evidenc e of the surface heterogeneity of clays. It is established that sites, iden tical from a crystallographic point of view, are different when the energy of the phenomenon is considered. The main interest of this work is to give for the first time a value of the hydration energy of cation onto clay surf aces. (C) 2000 Academic Press.