Methods for Removing Microplastics from Aqueous Media

The present study was conducted to review the methods of removing microplastics from aquatic environments. According to the literature review, common physical methods for removing microplastics from municipal and industrial effluents include ultrafiltration, reverse osmosis, and membrane bioreactors. Among chemical methods, the use of coagulants and flocculants in the treatment of microplastic wastewater has received more attention. In addition, one of the biological methods in removing microplastics is their removal using green algae and bacteria. The results showed that among the mentioned methods, the application of physical and biological methods has a higher priority due to their ease as well as economic efficiency. Many researchers consider the use of a combination of physical and biological methods to be the best option for removing microplastic wastes from aquatic environments. Due to the importance and application of physical methods in the removal of microplastics from aqueous media, pre-treatment steps and then the use of membrane separation techniques and membrane bioreactors (MBR) along with other treatment processes such as reverse osmosis, can significantly increase the efficiency of treatment methods. In the physical method, which is often membrane filtration, various factors are involved in the removal of microplastics, the most important of which are the properties of the membrane (membrane material, pore size, membrane thickness, surface properties) as well as the characteristics of the effluent (shape, size, mass, chemical composition, and concentration).