Study on the adsorption of metal ions onto azomethine functionalized magnetic nanoparticles in a single-and competitive-aqueous system

Abstract

This study evaluates the capability of azomethine functionalized magnetic nanoparticles to selectively remove heavy metal ions from aqueous solution containing complex matrix of contaminants and single contaminant system. The metal ions investigated were Pb 2+ , Zn 2+ , Cu 2+ and As 3+ . Batch adsorption studies involving the influence of pH and initial metal ion concentrations were assessed to determine the best experimental conditions. The adsorption capacities in a single-component system were higher than that obtained in a competitive adsorption system. The sequence of adsorption in both single and competitive component systems was Pb > Cu > As > Zn. This sequence was against the order obtained for their respective ionic radii in a competitive system. This was attributed to the fact that adsorption did not depend on the ionic radii of metal ions in solution but rather on the textural and functional characteristics of the adsorbent employed in this study. The result of influence of pH and initial metal ions concentration on the competitive removal of metal ions revealed that uptake of metal ions was pH and initial metal ion concentration dependent. Lastly, the removal of heavy metal ions from municipal wastewater demonstrated excellent adsorption efficiency confirming that azomethine functionalized magnetic nanoparticles exhibit good adsorption performance for the sequestering of complex matrix of contaminants.