Batch and fixed bed column studies on removal of Orange G acid dye by a weak base functionalized polymer

The performance of a weak base anion-exchange resin in removing Orange G dye from aqueous solutions in batch and column system was investigated. The adsorption capacity was found to depend on: pH, dye concentration, contact time, adsorbent dosage, electrolyte presence and temperature. The adsorption equilibrium is best described by the non-linear Langmuir isotherm model. At the optimum pH of 2, the maximum adsorption capacity was 1,076 and 1,218mgg(-1), at 20 and 50 degrees C, respectively. The adsorption kinetics could be described by the pseudo-second-order reaction model. The thermodynamic parameters indicated that adsorption is a spontaneous and endothermic process. FT-IR and SEM analyses provided additional information on adsorption mechanism and on morphological changes of the adsorbent. The breakthrough experimental results were processed by means of Thomas, Yoon-Nelson and Wolborska models. The reusability of the column was examined by conducting several cycles of adsorption and desorption (with 0.05M NaOH).