Applicability of the linear solvation energy relationships in the prediction for adsorption of aromatic compounds on activated carbons from aqueous solutions

A correlation capable of predicting adsorption capacities from the commonly available physicochemical properties of an adsorbate is of great significance to the engineering design of adsorption process. Apart from van der Waals force, dipole-dipole, induced dipole-dipole, and hydrogen-bonding donor-acceptor interactions exist between aromatic compounds (AOCs) and activated carbons. Correlations between the solubility normalized Freundlich affinity coefficients (KFS) of six AOCs on four activated carbons and the linear solvation energy relationship (LSER) variables of the AOCs were established. The modeling results demonstrate that the LSER model could be applied to predict the adsorption of AOCs on the activated carbons with KFS as a measure of the relative interaction strengths between the adsorbents and the adsorbates. Although derived from the properties of the adsorbates, the LSER modeling parameters were correlated with the surface chemistry of the studied activated carbons, suggesting that the LSER models could also reflect the natures of the adsorbents.