Theoretical Evaluation of Pillared Clay Adsorbents: Part I. The Microporosity of Al- and Ti-Pillared Montmorillonite

Pillared clays have become a well known class of porous materials. Due to the versatile porosity they seem to be complementary to zeolites and can be very useful for adsorption and catalytic processes. Despite intensive research, real industrial applications are still lacking. Somehow, the porosity of these pillared clays is not what was expected. The present study reports theoretical calculations, based on simple geometrical models in combination with experimental data, in order to obtain a better insight in the PILC structure and its limiting factors. Parameters such as interpillar free distance and maximum micropore volume were calculated and compared to experimental or literature data. The final goal is to find out the potential of pillared clays as adsorbents to be used as substituents or complements for zeolites. This part reports calculations, in terms of microporosity, performed for two types of pillared clays having completely different porosity properties: Al- and Ti-PILC.