Biopolymer mixture-entrapped modified graphene oxide for sustainable treatment of heavy metal contaminated real surface water

Abstract

The surface of graphene oxide (GO) features highly reactive carboxyl, epoxy, and hydroxyl groups; however, it cannot remove negatively charged species such as anion metals. Gadolinium (Gd) ions interact strongly with anionic species such as arsenic. The incorporation of gadolinium oxide to GO facilitates the removal of anion and cation heavy metals. However, the product was practically infeasible because to the thin, friable, and light flakes. To address these flaws, a polymer combination (Sodium Alginate (SA) and Carboxymethyl Cellulose (CMC)) was employed to bind GO–Gd2O3 into granules, the ability of which was verified to adsorb Cr(III), Pb(II), and As(V). The effective operating pH, dose, and temperature were 4.0, 1.4 g/L, and 298 K, respectively. Cr(III), Pb(II), and As(V) all had adsorption capabilities of 29.16, 158.73, and 36.77 mg/g, demonstrating gGO–Gd2O3 as effective granules for heavy metals removal from complex aquatic environments. According to the thermodynamic data, Cr(III) and As(V) adsorptions are endothermic, but Pb(II) adsorption is exothermic. The probable sorption mechanism was thoroughly discussed. The viability of produced materials was assessed by investigating their re-usability and use in real surface water. © 2022 Elsevier Ltd