Abstract

• Heavy metals are a concern in the environment as they accumulate and are non-biodegradable and thus bio-toxic. Many technologies have been employed for the removal of heavy metals in the environment. However, adsorption process is arguably the most promising and effective fundamental approach for the removal of heavy metals in wastewater treatment processes. An effective and facial method for removal of Pb2+ ion from aqueous solution is based on the prepared graphene oxides. The oxygenous functional groups on the surface of graphene oxides were primarily responsible for the sorption of metal ions. The graphene oxides were prepared from different graphite sources using modified Hummer’s method. The prepared graphene oxides (LGO, CGO, FGO) were used as adsorbent for removal of heavy metal ion (Pb2+ ion). The different graphite varieties (LGP, CGP, FGP) and the prepared graphene oxides (LGO, CGO, FGO) were characterized by XRD, UV-vis, FT IR and SEM. To obtain the optimum parameters for the removal of Pb2+ ion from model aqueous solution, adsorbent dosage, Pb2+ ion concentration and contact time were examined by complexometric titration method. The maximum removal capacity of Pb2+ ion using LGO, CGO and FGO were found to be 94.60 %, 95.66 % and 87.32 % at their optimal conditions. The removal capacity of Pb2+ ion on CGO and LGO was not quite different but FGO was lower than the other two. The obtained results demonstrated that the prepared graphene oxides can be used as an effective adsorbent for Pb2+ ion removal from water.