Relationship between hydration energy of zeolites and cation distribution in their crystals

A method is proposed for calculating the heat of immersion of zeolites in water from data on the composition and density of the zeolite framework. The phenomenon of localization of some of the zeolite cations in the unhydrated crystallographic positions is explained. For ferrisilicates with the ZSM-5 structure, the fraction of iron atoms in the framework has been estimated from data on the energy of hydration.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 2, pp. 174–179, March–April, 1993.