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Diffuse reflectance FTlR (DRIFT) spectra and potentiometric titration data have been obtained for montmorillonite samples pillared with different polycations. The IR spectra are interpreted after deconvolution into Voigt band profiles. The titration data are analysed using a stable numerical method for the solution of the adsorption integral equation (SAIEUS). The pK distributions obtained are used to characterize the acidic properties of the modified minerals to demonstrate the relationship between these properties and the coordination of cations in the pillaring species. Heat treatment enhances the acidity of the materials which may be the result of the rearrangement of pillars (dehydroxylation). The approach presented enables one to assess both qualitatively and quantitatively the number and strength of acidic sites present on the surface of pillared clays.

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The microstructural properties of carbons obtained by carbonization of poly(furfury1 alcohol) within different smectite matrices have been studied by gas adsorption. A method based on the analysis of the gas adsorption data using the relationship between the adsorption energy and micropore size, has been applied to evaluate micropore size distributions. The range of sensitivity of the method in relation to the adsorbate molecular size is discussed. Three adsorbates, CH, , CF, and SF,, having different molecular diameters were used and analyses of their adsorption data have been used either to cross-validate the results obtained or for complementary information. The relationships between the pore size distribution, the adsorption energy distribution and the isosteric heat of adsorption are discussed. The calculated pore size distributions for the synthetic carbons show differences related to the structure of the mineral matrix.

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