Removal lead and cadmium ions in industrial wastewater using graphene nano sheets

الملخص EN

Industrial wastewater effluents especially that contain heavy metals considered a foremost problem of water pollution in the worldwide environment.

Discharging this wastewater, that contains considerable heavy metals' concentrations into ground, water or streams and rivers causes deterioration of the ecological system.

The present study aimed to synthesized the graphene nano sheets by electrochemical method and used for removal of lead Pb+2 and Cadmium Cd+2 ions that found in industrial wastewater.

Graphene nano sheets synthetic in this study is characterized by X-ray diffraction XRD, scanning electron microscopy SEM, Raman spectroscopy and Fourier-Transformed Infrared Spectra (FT-IR).

The abundant oxygen-containing functional groups on the surfaces of graphene nanosheets and strong surface complexion played an important role in (lead and cadmium ions) adsorption.

Adsorption properties for (lead and cadmium ions) on graphene nanosheets were regularly investigated, including contact time, pH effect, adsorbent doses and initial concentrations for lead and cadmium solutions.

The experimental data were evaluated by Langmuir, Freundlich models in order to describe the equilibrium isotherms.

From the adsorption isotherms, the maximum adsorption capacities of lead ions on graphene calculated from Langmuir model were equivalent 476.19 (mg/g) at pH 6.2 and equilibrium contact time 35 min with adsorbent dose (40mg/L), and 188.679 (mg/g) at pH 5.2 and equilibrium contact time 40 min with adsorbent dose (20mg/L) for cadmium ions.

The results of the present study demonstrated that graphene has respectable qualifications to removal (Pb+2&Cd+2 ions) which found in industrial wastewater as compared to other adsorbents e.g.

activated carbon.