The recycle of spent Zn–C batteries and the synthesis of magnetic nanocomposite from graphene nanosheets and ferrite and its application for environmental remediation

Abstract

In this research work, the well-known manganese zinc ferrite Mn0.8Zn0.2Fe2O4 (MZF) magnetic material ferrite was prepared using an eco-friendly method from spent Zn–C batteries (SZCBs) and doped with the high surface area graphene oxide (GO) nanosheets to form MZF/GO magnetic nanocomposite. The prepared MZF/GO magnetic nanocomposite was characterized using DTA-TG, XRD, FT-IR, TEM, and VSM techniques for examining the morphological structure, functional groups, and magnetic properties of the prepared nanocomposite. The characterization results indicated the formation of the Mn0.8Zn0.2Fe2O4 ferrite, and GO, and the homogenous distribution of the ferrite on the GO nanosheets. MZF/GO magnetic nanocomposite was then used as a solid adsorbent for removing Acid Red (AR) dye from water. The results presented the suitability of the pseudo-second-order kinetic model, exothermic, electrostatic, and the physical nature adsorption process, with a removal capacity of 49.9 mg AR dye per g MZF/GO magnetic nanocomposite. The thermodynamics of the adsorption process showed the spontaneity of the process, with a negative entropy change value of −63.7 J/mol.K, negative enthalpy change value of −34.5 kJ/mol, and negative Gibbs free energy change value of −17.5 kJ/mol, indicating that the adsorption of the AR dye by MZF/GO magnetic nanocomposite is enthalpy-driven-process. Moreover, MZF/GO magnetic nanocomposite could be used for the remediation of real environmental water polluted with AR dye, and also could be used for five consecutive cycles with high efficacy for times for the adsorption/removal of AR dye.

Keywords

• Ferrite
• Graphene oxide
• Water treatment
• Acid red dye
• Kinetics
• Thermodynamics