Porosity and thermal stability of PILCs prepared with clays from different origins and different metal–polyhydroxycationic species ofAl and Al/Ce

Abstract

Montmorillonites from different origins have been pillared with polyhydroxycations of Al and Al/Ce in order to preferentially obtain pillared clays with large pores and good thermal stability. The precursors of the stable materials,i.e. the intercalating species, and the intercalated but not calcined samples, were studied by differential scanning calorimetry. The textural properties of the materials obtained with different pillaring solutions, and calcined at 500 and 700 °C, were studied by nitrogen adsorption. It is shown that depending predominantly on the oligomer composition and much less on the type of parent material, solids with different meso- and microporous volumes can be obtained with structures that, in some cases, present specific surface areas higher than 300 m² g^–1 at 700 °C.

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