Comparison of the adsorption of humic acids from aqueous solutions on active carbon and activated charcoal cloths

Abstract

Batch experiments were conducted to determine the adsorption of humic acids from aqueous solutions by active carbon, activated charcoal cloth, and textile. The adsorption isotherms and adsorption kinetics curves of humic acids on these adsorbents at 25°C have been determined. The adsorption capacities of the ACC samples are much lower than that of the active carbon. Effective intraparticle diffusion coefficients of humic acids of 1.2 × 10 −7 and 2.5 × 10 −10 cm 2/ s have been calculated for active carbon and activated charcoal cloth, respectively, from the kinetic curves. The adsorption behavior and different diffusion coefficients are consequences of their various textural characteristics. Only the surface area corresponding to mesopores and macropores is effective, the micropores are inaccessible to humic acids.