The theory underlying the absorption behavior of carbons is discussed as a basis for quantitative analysis of their adsorption properties and microporous structure. The equations of the theory of volume filling of micropores for homogeneous and inhomogeneous microporous structures and a rational me
Microporous structures and absorption properties of carbonaceous adsorbents
โ Scribed by M.M. Dubinin
- Publisher
- Elsevier Science
- Year
- 1983
- Tongue
- English
- Weight
- 759 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0008-6223
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โฆ Synopsis
Two
new independent methods for determining the surface area of micropore walls (the geometrical surface of micropores) of carbonaceous adsorbents have been proposed. Their satisfactory agreement has been substantiated experimentally. A comparative analysis of adsorption isotherms of benzene at 293 K on model carbonaceous micro-and supermicroporous adsorbents and of isotherms on mesoporous carbonaceous adsorbents with equal geometrical surface areas has been carried out. A quantitative estimate, under comparable conditions, of the increase in adsorption values in micro-and supermicropores as compared with nonporous or mesoporous adsorbents has been given for the first time.
The formal applicability of the BET equation to adsorption isotherms of nitrogen at 77 K and benzene at 293 K on model carbonaceous microporous adsorbents, whose micropore geometrical surface area changed almost four-fold, has been shown. The determined monolayer capacities were close to the preassigned constant limiting adsorption values for the filled micropores. As a result the specific surface areas according to BET for the adsorbents under consideration were nearly equal.
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