| The present study investigated and determined the ability of existing predictive and correlative models to calculate equilibrium sorption data of Methylene Blue, Rhodamine B, and Malachite Green Oxalate onto a commercially available activated carbon Filtrasorb 400 and an agricultural byproduct made from acid activation of almond shells. Single, bi-solute and tri-solute system experimental data were obtained by conducting batch experiments in their aqueous solutions. Freundlich, Langmuir, Redlich-Peterson, and Toth isotherms coupled with five nonlinear error measures were evaluated in single-solute systems for experimental data derived from two analytical methods, namely the UV spectrophotometer and the TOC analysis. For the multi-solute systems, nonlinearly determined single-component parameters of the Freundlich, the Langmuir and the Redlich-Peterson isotherms coupled with their multi-component forms and interaction factor were used to correlate multi-component experimental data.; The empirical extended Freundlich model produced the closest fit to the binary data in each case. In the case of ternary system, the extended Redlich-Peterson model provided a very close fit to the experimental data of each component. Over all, optimization coupled with nonlinear error regression analysis provided a simple, robust and computationally effective technique of producing optimal fitting parameters for sorption models from multi-component equilibrium data and single-component optimal parameters. |
