초록 |
The treatment of water pollutants such as heavy metal ions has become a critical issue to maintain a healthy environmental system. Herein, we report a facile preparation of polyethyleneimine(PEI) functionalized microgel capsules as an effective adsorbent of heavy metal ions from water, using a microfluidic approach. To synthesize the PEI-coated microgel capsules, the middle phase of double emulsions composed of polyvinyl alcohol(PVA) and glutaraldehyde(GA) was exposed to hydrogen ions, thus changing from liquid to a gel. Subsequently, PEI molecules were immobilized at the surface of the hydrogel by the reaction with carbonyl groups (i.e., Schiff base formation). After adsorption of heavy metal ions, the microgel capsules were readily separated from the suspension by applying buoyancy difference and magnetic force. The adsorption behaviors of resultant microcapsules were evaluated, and the adsorption efficiency of microgel capsules was studied by varying process parameters. |