Porous Tb-MOFs with abundant nitrogenous functional groups show efficient Pb2+ removal.

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 Fe 3 O 4 nanoparticles (Fe 3 O 4 −NH 2 ), the as-prepared MPPs with rich pore hierarchy were employed to removal Pb 2+ and Cd 2+ from aqueous solution. The MPPs display outstanding removal capacities toward Pb 2+ (257 mg/g) and Cd 2+ (129 mg/g) within 15 min, and the encapsulated Fe 3 O 4 −NH 2 nanoparticles endow the MPPs with the ability of magnetic separation (30.15 emu/g). Additionally, the results indicate that the adsorptions of Pb 2+ and Cd 2+ are strongly dependent on pH and ionic strength, demonstrating that the interactions of Pb 2+ and Cd 2+ were mainly dominated by outer-sphere surface complexation and electrostatic attraction. The adsorption process is revealed by thermodynamic parameters to be spontaneous and endothermic. Further study demonstrates that the adsorption is involved in ion-exchange and cation−π interactions (between heavy metals and aromatic ring) on the surface of MPPs. Thus, feasible preparation of the MPPs with high adsorption capacities, excellent regeneration, and easy separation properties opens a new expectation in the potential application for engineering.