Poly(methacylic acid-co-maleic acid) grafted nanofibrillated cellulose as a reusable novel heavy metal ions adsorbent

•Aerogel adsorbent based on nanofibrillar cellulose was prepared.•The cellulose aerogel was modified by grafting methacrylic and maleic acid to boost the adsorption capacity.•The modified aerogel showed improved adsorption toward wide range of heavy metal.•The cellulose aerogel could to be readily regenerated and reused without any loss of the adsorption capacity.

A poly(methacrylic acid-co-maleic acid) grafted nanofibrillated cellulose (NFC-MAA-MA) aerogel was prepared via radical polymerization in an aqueous solution using Fenton's reagent. The ensuing aerogel, in the form of a rigid porous material, was characterized by FTIR and NMR and used as an adsorbent for the removal of heavy metals from aqueous solutions. It showed an efficient adsorption, exceeding 95% toward Pb2+, Cd2+, Zn2+ and Ni2+ when their concentration was lower than 10 ppm and ranged from 90% to 60% for a metal concentration higher than 10 ppm. Over 98% of the adsorbed metal ion was recovered using EDTA as a desorbing solution, and the subsequent washing allowed the aerogel to be reused repeatedly without noticeable loss of adsorption capacity. It was concluded that the (NFC-MAA-MA) aerogel may be used as a high capacity and reusable sorbent material in heavy-metal removing processes.