An Overview of Surface-Functionalized Magnetic Nanoparticles: Preparation and Application for Wastewater Treatment

The removal of contaminant and recovery of valuable matters from wastewater remain a challenge in the field of industrial production. Among the developed technologies, adsorption method is of interest for researchers due to its low-cost and facile operation. However, the traditional adsorbents always meet the problem of difficult recycling. Nowadays, surface functionalized magnetic nanomaterials have become a new kind of adsorbents with the potential application in the wastewater treatment because of their large surface area, high stability, weak coagulation, and especially reusability due to its super-paramagnetic properties in a magnetic field. The extraction capacity of pollutants is mainly related to the features of functional groups grafted on the surface of Fe3O4 nanoparticles. This review mainly focuses on recent progress on the functional modification methods of magnetic Fe3O4 nanoparticles by inorganic molecules, small organic molecules, and organic polymer materials. The advantages and disadvantages of magnetic Fe3O4 nanoparticles modified by various functional groups, application and interaction mechanism in the wastewater treatment are also reviewed. Finally, the development trend of surface modified magnetic adsorption materials in the future wastewater treatment field is prospected.