Facile microfluidic synthesis of copolymer hydrogel beads for the removal of heavy metal ions

摘要

A novel and recyclable poly(polyethylene glycol diacrylate/maleamic acid) (p(PEGDA/MALA)) copolymer hydrogel beads were for the first time synthesized through a microfluidic method and used for the removal of heavy mental ions from water. The monodisperse and size-controlled pregel droplets were firstly prepared by a microfluidic device and then polymerized to the hydrogel beads under UV irradiation. The synthesized p(PEGDA/MALA) hydrogel beads were characterized using various techniques and showed good adsorption property for Pb2+. The influencing factors on the adsorption process of Pb2+ were investigated in detail. The experiment results indicated that Pb2+ adsorption process was pH dependent, and agreed with the Langmuir monolayer model and pseudo-second-order equation. The adsorbing mechanism of copolymer hydrogel beads for Pb2+ mainly resulted from the electrostatic interaction and chelation action. The competitive adsorption experiment indicated that the affinity order in multicomponent adsorption was Pb2+> Cu2+> Cd2+. The well-designed p(PEGDA/MALA) copolymer hydrogel beads had excellent adsorption capacity and high recyclability and showed a promising application prospect in the decontamination of heavy metal ions in water.