Facile synthesis of flowered mesoporous graphene oxide-lanthanum fluoride nanocomposite for adsorptive removal of arsenic

In this work, the surface of graphene oxide was functionalized with lanthanum to produce porous flowered graphene oxide-lanthanum fluoride (GO-LaF) nanocomposite for adsorptive removal of As(V) from aqueous system. GO-LaF nanocomposite was characterized by TEM, SEM, XRD, and XPS analysis. Maximum adsorption capacity for As(V) was 18.52 mg g(-1), (at 298 K) and was dependent on the solution pH, adsorbent mass, contact time and As(V) concentration. Pseudo-second-order kinetic model provided excellent kinetic data fitting. The isotherm data were well-fitted to the Langmuir equation. Adsorption results obtained at different conditions suggest that As(V) adsorption onto GO-LaF occurs through mixed processes such as electrostatic, ion-exchange, and surface complexation. Electrostatic interactions were predominantly involved in the adsorption process at low pH while surface complexation and/or ion-exchange were predominantly involved above neutral pH. (C) 2019 Published by Elsevier B.V.