A Water-Based Synthesis of Hybrid Silica/Hyperbranched Poly(ethylene imine) Nanopowder for Heavy Metal Sorption from Aqueous Solutions

A novel hybrid, water-based, sol-gel method was developed for the synthesis of functionalized silica with advanced adsorptive capacities towards heavy metal ions. The study employs the hyperbranched poly(ethylene imine) (HBPEI) as a reactive template for the synthesis of silica. The reaction was followed by FTIR, whereas the material was evaluated in terms of its microstructure and adsorptive properties. The results revealed a very potent adsorbent that can remove heavy metal ions (namely, Pb, Cu, and Zn) from water in a fast and efficient way. Greater selectivity was observed for lead, whereas the maximum adsorption capacities calculated from the Langmuir model were 833.3, 502.5, and 193.4 mg/g for lead, copper, and zinc, respectively