Electrochemical Synthesis of Graphene from Waste Discharged Battery Electrodes and Its Applications to Preparation of Graphene/Fe3O4/Chitosan-Nanosorbent for Organic Dyes Removal

In this work, graphene was synthesized from waste discharged battery electrodes using an electrochemical exfoliation method. The graphene product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and adsorption activity. For application, as-synthesized graphene was used for preparation of Fe3O4/graphene/chitosan (FGC) nanocomposite as a recyclable-nanosorbent for removal of organic dyes including methylene blue (MB), methyl orange (MO), brilliant blue FCF (E133), eriochorome black T (EBT) and thymol blue (ThB) from aqueous solution. The obtained results shown that the FGC adsorbent is more attractive to MB and EBT than other evaluated dyes. At optimized conditions, FGC can adsorb MB at maximum adsorption capacity (q(max)) of 94.16 mg g(-1) and the remaining adsorption efficiency for the 5th cycle was 74.81% compared to that of the pristine FGC nanosorbent. Moreover, the FGC nanocomposite was also used to remove MB from real wastewater with high removal efficiency. This performance implies a high application potential of synthesized graphene from waste graphite for environmental treatments.