POROUS STRUCTURE OF POLYARYLAMIDE-BASED ACTIVATED CARBON-FIBERS

Activated carbons were prepared from two polyarylamide fibres (Kevlar and Nomex) by carbonization and subsequent steam activation to 25 and 50% burn-off. The porous structure of the carbons has been investigate d by physical adsorption of CH2Cl2 and N2O at 293 K and immersion calo rimetry into liquids of different molecular dimensions. The activated fibres have good sorptive capacities and relatively narrow micropores. The materials resulting from activation at low degrees of burn-off co uld therefore be of great interest in gas separation, owing to their m olecular-sieve properties. Compared to industrial activated carbons, t he fibres are hydrophilic and have small external surface areas. Copyr ight (C) 1996 Published by Elsevier Science Ltd