Microwave-assisted synthesis of polyethylenimine-grafted nanocellulose with ultra-high adsorption capacity for lead and phosphate scavenging from water

Herein, polyethylenimine-grafted nanocellulose (PEIMW@NCMW) was synthetized through microwave-assisted synthesis, which was employed for Pb(II) and phosphate scavenging from water. Characterization results exhibited that the original pomegranate peel-derived cellulose could be transformed to nanometer level by microwave radiation and the amino groups were successfully grafted on the nanocellulose evenly. The adsorption performance of PEIMW@NCMW possessed outstanding improvements over that of original nanocellulose with maximum adsorption capacities reaching 916.02 mg/g for Pb(II) and 278.89 mg/g for phosphate. Furthermore, the PEIMW@NCMW had high tolerance to various co-existing ions and could maintain over 94% removal efficiency during four regeneration cycles. Additionally, the Pb(II) uptake onto PEIMW@NCMW was associated with electrostatic attraction, complexation and pore-filling, whereas high phosphate capture was achieved via H-bonding, complexation and electrostatic attraction. In summary, PEIMW@NCMW was deemed as a potential adsorbent with excellent adsorption capacity for remediation of Pb(II) and phosphate polluted water.