Microporous structures of carbonaceous adsorbents

✍ Scribed by M.M. Dubinin; G.M. Plavnik

• Publisher: Elsevier Science
• Year: 1968
• Tongue: English
• Weight: 735 KB
• Volume: 6
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(68)90302-3

✦ Synopsis

The microporous structure of coals (anthracite and lean coal) carbonized and activated with water vapour at 900°C was investigated by the small-angle X-ray scattering and adsorption methods. As distinct from the previously studied active carbons from sucrose possessing uniform microporosity (inertia radii R =6-7 A), coals are characterized by a considerably greater polydispersity of micropores. Small-angle X-ray scattering data, which were in agreement with the results of the theoretical analysis of benzene adsorption isotherms, revealed coarser micropores of R=ll-14 A along with fine micropores of R=6-7 A, in active coals. At low degrees of activation, fine micropores are predominant in the activeycarbons obtained. As bum-out increases the fraction of coarser micropores grows. It is believed that the size polydispersity of active coal micropores, which roughly corresponds to the radius range R =4-l 5 A, stems from the non-homogeneity of the structure of the initial products used for activation, -.

i.e. anthracite and lean coal.