Microporous texture of activated carbon fibres prepared from Nomex aramid fibres

Nomex [poly (m-phenylene isophthalamide)] was used as a feedstock for the p reparation of activated carbon fibres (ACFs). For this purpose, pyrolysis u nder inert atmosphere (Ar) was followed by activation with CO,. Two differe nt series of ACFs were prepared by changing the pyrolysis (1123 or 1173 K) and activation temperatures (50 K below pyrolysis). The resulting ACFs were characterised by N-2 (77 K) and CO2 (273 K) adsorption. The surface area a nd pore volume increase progressively upon activation: no maxima were found over the burn-off range studied (0-74%). ACFs prepared from Nomex are micr oporous and exhibit more uniform and narrower porosity than those prepared from Kevlar flock under equivalent conditions. It is believed that these ma terials could constitute a suitable precursor for carbon molecular sieves. (C) 2000 Elsevier Science B.V. All rights reserved.