Importance of Surface Area and Pore Size Distribution of Resin for Organic Toxicants Adsorption

Adsorption of benzoic acid and reactive brilliant blue 4 (RBB4) by hypercrosslinked resins and macroporous resins was examined. Micropore areas were much higher in the hypercrosslinked resins than macroporous resins while the pore volume and average pore diameter of macroporous resins were superior to the hypercrosslinked resins. The investigation showed that the pore size distributions of the resins significantly influenced the adsorption capacity of adsorbents. Adsorption of benzoic acid was dominated by BET surface area and the micropore area while the adsorption of RBB4 shifted to a pore-size-dominant process. The maximum mol adsorption capacities of benzoic acid were all higher than those of RBB4 by the resins, showing the influence of the molecular dimension on adsorption. The adsorption thermodynamic parameters were calculated and it revealed that the adsorption was an exothermic, spontaneous, and more ordered process. Adsorption kinetics and elution processes were also investigated for establishing the appropriate adsorption conditions for purifying wastewater containing benzoic acid or RBB4.