Application of magnetic graphene in the field of wastewater treatment: A review

Water shortage and pollution are the main problems facing the world. Adsorption is a promising wastewater treatment technology. Graphene is a good adsorbent. However, graphene is difficult to separate from water, which limits its application. Magnetic graphene not only has excellent adsorption capacity, but also can be quickly separated from aqueous solution by increasing the external magnetic field, which solves the limitations of traditional adsorbents. In addition, the selectivity and efficiency of MGO for specific pollutants were enhanced by the functionalization of materials such as chitosan, cyclodextrin and EDTA. For example, the removal rates of Pb (II), Hg (II) and Cu (II) by EDTA-functionalized MGO were 96.2 %, 95.1 % and 96.5 %, respectively. This review breaks through the limitations of single pollutant research and scientifically divides the pollutant system into three categories: ions (heavy metal ions, radioactive metal ions, and arsenic), organic pollutants (dyes, antibiotics, and aromatic compounds), and agricultural pollutants (herbicides, pesticides). The antibacterial properties of magnetic graphene were systematically described for the first time, revealing its ability to remove pathogenic microorganisms such as Escherichia coli (sterilization rate up to 95 %). In summary, MGO has broad prospects in the field of wastewater treatment.