A novel material poly(N-acryloyl-L-glycine)-brush grafted N-doped magnetic biochar by surface-initiated RAFT polymerization for efficient elimination of heavy metal ions

To remove toxic and non-degradable heavy metal ions, a novel magnetically responsive polymer brush based on eco-friendly biochar was designed and prepared using reversible addition fragmentation chain transfer polymerization method. Subsequently, functional groups, structures, specific surface areas and morphologies of the material were characterized by FT-IR, SEM, BET, Raman and TGA. Then, the material was applied to remove Cr6+ and Cu2+. Additionally, a series of factors that might affect the adsorption were also explored, such as pH, salt concentration, time and temperature. Results concluded that the prepared material with abundant functional groups had excellent adsorption capacity of 34.84 and 112.94 mg/g, respectively for Cr6+ and Cu2+ at 318 K. Finally, characterization results of FT-IR and XPS indicated that adsorption mechanisms were primarily attributed to ion exchange, electrostatic interaction, cation-π bonding and hydrogen bonding. Based on experimental results, prepared material had excellent adsorption capacity, high cycle performance, quick magnetic separation performance, making it as a promising material for sewage treatment.