Absorption performance of DMSA modified Fe3O4@SiO2 core/shell magnetic nanocomposite for Pb2+ removal

The purpose of this study is to explore the adsorption performance of meso-2, 3-dimercaptosuccinic acid (DMSA) modified Fe3O4@SiO2 magnetic nanocomposite (Fe 3 O 4 @SiO 2 DMSA) for Pb 2+ ions removal from aqueous solutions. The effects of solution pH, initial concentration of Pb2+ions, contact time, and temperature on the amount of Pb2+ adsorbed were investigated. Adsorption isotherms, adsorption kinetics, and thermodynamic analysis were also studied. The results showed that the maximum adsorption capacity of the Fe 3 O 4 @SiO 2 DMSA composite is 50.5 mg/g at 298 K, which is higher than that of Fe3O4 and Fe 3 O 4 @SiO 2 magnetic nanoparticles. The adsorption process agreed well with Langmuir adsorption isotherm models and pseudo second-order kinetics. The thermodynamic analysis revealed that the adsorption was spontaneous, endothermic and energetically driven in nature.