Optimization of lead removal from aqueous solution using goethite/chitosan nanocomposite by response surface methodology

摘要

This work investigates goethite/chitosan nanocomposites for their use in lead removal from aqueous solutions. Goethite nanoparticles were synthesized and characterized by FTIR, DLS, and SEM. Goethite nanoparticles were identified as nanospheres with the average diameter of 10-60 nm. The optimum conditions were determined using response surface methodology (RSM) based on three-variable-three-level Box-Behnken design (BBD). The effects of three variables, i.e., initial solution pH, adsorbent mass and initial concentration of Pb(II) ions on the removal efficiency for Pb(II) ions were evaluated. The optimal conditions for the lead removal were found to be 6,0.05 g, and 74.4 mg/L, for the initial solution pH, adsorbent mass and the initial concentration of Pb(II) ions, respectively. Under these conditions, maximum lead removal efficiency was obtained to 98.26% that was in respectable agreement with the model (97.19%). The modified quadratic model exhibited excellent stability for Pb(II) adsorption by goethite/chitosan nanocomposite. The results of adsorption study by goethite/chitosan nanocomposite revealed that Pb(II) uptake was enhanced by chitosan film using goethite nanoparticles. (C) 2015 Elsevier B.V. All rights reserved.