Magnetic Porous Polymers Prepared via High Internal Phase Emulsions for Efficient Removal of Pb2+ and Cd2+

Magnetic porous polymers (MPPs) were successfully fabricated by a facile strategy of the high internal phase emulsions (HIPEs) technique. The microstructure, chemical composition, and magnetic properties of the MPPs were characterized. Impregnated with poly(styrene-divinylbenzene), stabilized by the amine-functionalized Fe3O4 nanoparticles (Fe3O4–NH2), the as-prepared MPPs with rich pore hierarchy were employed to removal Pb2+ and Cd2+ from aqueous solution. The MPPs display outstanding removal capacities toward Pb2+ (257 mg/g) and Cd2+ (129 mg/g) within 15 min, and the encapsulated Fe3O4–NH2 nanoparticles endow the MPPs with the ability of magnetic separation (30.15 emu/g). Additionally, the results indicate that the adsorptions of Pb2+ and Cd2+ are strongly dependent on pH and ionic strength, demonstrating that the interactions of Pb2+ and Cd2+ were mainly dominated by outer-sphere surface complexation and electrostatic attraction. The adsorption process is revealed by thermodynamic parameters to be spo...