Characterization of the porous structure of two naturally occurring materials through N2-adsorption (77 K) and gas chromatographic methods

The method of adsorption of N-2 (77 K) and hydrocarbon C-6 (295 K) has been used to study the porous structure of two Mexican natural adsorbents: ANAVE and ZAPS. It was established that ANAVE is a mesoporous adsorbent, and ZAPS is essentially microporous with approximate to 85% of micropore contents. The micropore Volume (Dubinin) coincides with the capacity of Langmuir monolayers. The microporous structure also was characterized by t-method, "film surface area method", and chromatographic separation tests of the atmospheric air and the mixture of n-hexane, cyclohexane and benzene. It was established (XRD) that the principal crystalline phase in ZAPS corresponds to the erionite and that this natural adsorbent can be applied in processes of great practical interest, such as the separation of n-paraffin from cyclic and aromatic hydrocarbons. The sample ANAVE is a non-crystalline material (XRD). (C) 2001 Published by Elsevier Science B.V. All rights reserved.