Use of magnetic nanomaterials in wastewater treatment: a review

The growing need for clean water, as well as the mounting problems of water pollution, have prompted the development of innovative and efficient water treatment technologies. The unique qualities of magnetic nanomaterials (MNMs), including their large surface area, magnetic responsiveness, and ease of functionalization, have made them a potential option. MNMs are produced via chemical, physical, or biological means. MNMs are used in membrane filtration, adsorption, catalysis, and magnetic separation for the treatment of wastewater. They may adsorb contaminants, act as catalysts, improve membrane filtering performance, and enable facile recovery and reuse via magnetic separation. MNMs have high specificity, efficiency, and recyclability, but they confront environmental and health risks, high production costs, and scaling concerns. Therefore, the ongoing research must focus on eco-friendly approaches, improving stability, studying synergistic effects, and conducting risk analysis of MNMs to ensure safe use. Moreover, the MNMs investigated are only applicable for synthetic or small-scale wastewater treatment. Only a few MNMs are operating at an industrial level; therefore, more investigation is suggested for the applicability of MNMs on a large scale and real wastewater treatment.