Simultaneous Removal of Ibuprofen and Bisphenol a from Aqueous Solution By an Enhanced Cross-Linked Activated Carbon and Reduced Graphene Oxide Composite

Abstract

Reduced graphene oxide-modified activated carbon (RGO/AC) composites are promising materials for organic micropollutants removal from aqueous systems. Herein, several green cross-linking reagents, such as an extract solution (ES) originating from fermentative tubers and cereal wastes, are developed to enhance the cross-linking for AC and RGO. These processes are also conducive to the valorization of tubers and cereal residues. The reactivity of RGO/AC composites was evaluated for bisphenol A (BPA) and ibuprofen (IBP) adsorption from an aqueous solution in single and binary systems. The results show that the cross-linking speed and degree for AC and RGO by ES originating from fermented cassava (RGO/AC1) and wheat residues (RGO/AC2) are better than that obtained for natural ES. Characterization results show that the specific surface area of the RGO/AC composites is increased with the cross-linking phenomenon. The RGO/AC composites show a higher BPA and IBP removal efficiency and capability than pristine AC. Moreover, the RGO/AC composite shows a higher anti-interference capability for BPA and IBP adsorption than pristine AC. The adsorption of BPA and IBP by AC/RGO is dominated by the pseudo-second-order kinetics and Freundlich isotherms in both single and binary systems.  Hydrophobic and electrostatic interactions are dominant between BPA, IBP molecules, and adsorbents.

Keywords: activated carbon, Graphene oxide, Extract solution, Adsorption, Bisphenol A and Ibuprofen