A novel magnetic sepiolite/Fe2O3 composite for adsorptive removal of lead(II) ions from aqueous solutions

Abstract

: Lead is one of the most frequently encountered toxic heavy metals that requires immediate remediation. To remediate wastewater, clay minerals are the preferred adsorbents. In this study, the removal of lead from aqueous solutions via adsorption was investigated using raw and iron-modified Turkish sepiolite. The aim of this study was to examine the effect of modification and environmental conditions on the sorptive properties of sepiolite samples. Initially, the raw sepiolite (Sep) and magnetic sepiolite/Fe 2 O 3 composite (MagSep) prepared by the co-precipitation method were characterized using mineralogical and petrographical means, and the physico-chemical properties were determined. Then, the batch adsorption of lead (Pb 2+ ) ions on the sepiolite samples were examined under various conditions (solution pH, adsorbent dosage, contact time, initial Pb 2+ ion concentration, temperature, shaking rate). The adsorption capacity of MagSep was found to be higher than that of Sep under all experimental conditions. The results showed that the adsorption process followed a pseudo-second-order kinetic model,