Design and model parameters estimation for fixed–bed column adsorption of Cu(II) and Ni(II) ions using magnetized saw dust

Abstract

Fixed-bed column studies were performed using magnetized sawdust (Fe3O4–SD) as adsorbent for removal of Cu(II) and Ni(II) ions form aqueous solutions. Breakthrough curves were obtained by performing experiments in order to evaluate the influence of adsorbent bed height (2, 4, 8 cm), metal ion concentration in feed solution (10, 20, 30 mg/L), and feed flow rate (15, 20, 25 mL/min) for adsorption of Cu(II) and Ni(II) ions onto Fe3O4–SD adsorbent. Adsorption kinetics was analyzed using Bohart–Adams, Thomas, and Yoon–Nelson models. Kinetic data correlated well with both Thomas and Yoon–Nelson models, while Bohart–Adams model poorly predicted the model operation. Saturation loading capacity of adsorbent bed decreased with increase in adsorbent bed height, metal concentration in feed, and feed flow rate. Both mass transfer zone (MTZ) height and height of unused bed (HUNB) noticeably increased with increase in the values of the parameter studied. The results showed that reduced MTZ height and lowest HUNB are suitable for operating the column satisfactorily. © 2015 Balaban Desalination Publications. All rights reserved.