| Abstract
| - The mechanism of water adsorption is analyzed in a range of activated carbons differing widely in the relativeproportions of narrow and wide micropores, mesopores, and macropores. They also display different degreesof surface functionality. By assuming that the adsorbed phase in micropores is “ice-like”, it is shown that thewhole micropore volume is filled with water at a P/P0 of about 0.82, at which point capillary condensationmay begin. However, surface complexes control the wetting of the mesopore walls by adsorbed water andcan influence the condensation process. Condensation in macropores may also occur at P/P0 values above0.95. The extent of meso-/macropore filling depends on the surface complexes. The volume filling processis progressive and in micropores is consistent with the theory of volume filling. The adsorption process wasanalyzed by interpreting the nitrogen isotherms systematically measured on samples of different pore structurewith progressively increasing amounts of preadsorbed water up to saturation.
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