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

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 Pb. The influencing factors on the adsorption process of Pb were investigated in detail. The experiment results indicated that Pb 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 Pb mainly resulted from the electrostatic interaction and chelation action. The competitive adsorption experiment indicated that the affinity order in multicomponent adsorption was Pb>Cu>Cd. 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. [ABSTRACT FROM AUTHOR]