Adsorption characteristics of phenol on novel corn grain-based activated carbons

The adsorption of phenol on highly porous novel corn grain-based activated carbons (CG-ACs) (>2000 m(2)/g) were assessed in a batch mode. The optimum conditions for the adsorption of phenol on R-series (R-1/2, R-1/3, and R-1/4) CG-ACs were determined by analyzing the various adsorption conditions such as the adsorption temperature (293.15-313.15 K), initial solution concentrations (25-150 mg/L), and initial pH (3-12) of the solution. In addition, effects of CG-AC properties such as physical properties, energetic heterogeneity nature and surface chemistries on phenol adsorption were also investigated. In overall, it was found that the influences of physical properties and energetic heterogeneity nature of CG-ACs on phenol adsorption are considerably high compared to their surface chemistry. More specially, the increase in phenol adsorption capacity with increasing fraction of microporosity ranging from 3 to 11 angstrom, is likely due to the micropore filling, was noted. The Langmuir model well fitted with the experimental results compared to the Freundlich. Besides, the pseudo second-order equation was successfully used to represent the results of kinetic studies. (C) 2009 Elsevier Inc. All rights reserved.