Evidence of textural modifications of an activated carbon on liquid-phase oxidation treatments

Two series of samples were prepared by means of oxidation of a parent activated carbon with either HNO3 or H2O2. An important effect of the HNO3 treatment temperature on the textural properties of the resulting samples was found, since below 333 K only the mesoporous region was affected, whereas at 363 K a generation of micropores and a loss of mesopores took place. The textural properties were strongly affected when reflux conditions were applied. The effect of the H2O2 treatment concentration on the textural properties was low as compared with the effect of the HNO3 treatment temperature. In both treatments, modifications on the adsorption distribution potentials obtained by the Dubinin-Astakhov formalism were observed. (C) 1997 Elsevier Science B.V.

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