Adsorption from aqueous phenol and aniline solutions on activated carbons with different surface chemistry

The weak acid and base studied do not behave symmetrically: the uptake of phenol exhibits a maximum, while a monotonic increase with pH was found with aniline. The pH dependence of the adsorption capacity and the interaction parameter is stronger for aniline than for phenol. The lower water solubility of the aniline does not result in higher adsorption capacity. Its maximum uptake and interaction parameter are lower than those of phenol.