Description of adsorption equilibrium of PAHs on hypercrosslinked polymeric adsorbent using Polanyi potential theory

In this research, static adsorption of three polycyclic aromatic hydrocarbons (PAHs), naphthalene, acenaphthene, and fluorene, from aqueous solutions onto hypercrosslinked polymeric adsorbent within the temperature range of 288–308 K is investigated. Several isotherm equations are correlated with the equilibrium data, and the experimental data is found to fit the Polanyi-Dubinin-Manes model best within the entire range of concentrations, providing evidence that pore-filling is the dominating sorption mechanism for PAHs. The study shows that the molecular size of adsorbates has distinct influence on adsorption capacity of hypercrosslinked polymeric adsorbent for the PAHs; the larger the adsorbate molecular size, the lower the adsorption equilibrium capacity. Based on the Polanyi-Dubinin-Manes model, the molecular size of adsorbates was introduced to adjust the adsorbate molar volume. Plots of q _v vs. (σε/V _s) are collapsed to a single correlation curve for different adsorbates on hypercrosslinked polymeric resin. Supported by the National Natural Science Foundation of China (Grant No. 50408025)