Polyethyleneimine functionalized crescent-shaped microgel templated by Janus emulsion for rapid eliminating lead from water

Abstract

Microgels is recognized as one of the most important functional sorbents for heavy metal removal from contaminated water. However, their simple synthesis and group-specific modifications are still challenging. Herein, polyethyleneimine (PEI) functionalized crescent-shaped microgel sorbent (CPNIPAM-AGE-PEI) was prepared for rapid eliminating Lead ions (Pb(II)) from water. CPNIPAM-AGE-PEI (diameter about 10 µm) exhibited well-defined crescent morphology with preferred orientation of cavity from DEX phase. The adsorption kinetics and isotherm data of Pb(II) on CPNIPAM-AGE-PEI demonstrate that the unique crescent-shaped structure enhanced the kinetic performance, achieving 89.52 % of the saturation adsorption capacity in the first 30 min. A favorable and monolayer adsorption capacity at 298.15 K was 52.27 mg g−1, and chemisorption based on N atoms of functionalized PEI chains may be the main adsorption mechanism. In the case of competition with other ions, CPNIPAM-AGE-PEI has excellent selective adsorption capacity for Pb(II), and the adsorption capacity remained above 87 % after five adsorption/desorption cycles.