Review of Advanced Techniques for Removal of Microplastics in Water and Wastewater

Plastic particles (microplastics and nanoplastics) are considered as an emerging pollutant and a serious threat to the environment which are distributed all over the world. The presence of plastic particles in various ecosystems, especially aquatic environments, is very life-threatening to diverse organisms. Therefore, it is urgently needed to find an effective treatment technology or to develop and improve conventional treatment technologies for the removal of microplastics and nanoplastics. So far, the scientific community has carried out some research on various options for treatment and removal of plastic particles. Currently, multiple technologies have been developed by researchers, including physical, chemical and biological, among which, few have shown good efficiency for removing microplastics and nanoplastics. Filtration technology has a various removal efficiency, but a relatively high cost due to membrane fouling and replacing new filters. The magnetic absorption and separation process is also considered as a simple removal method; however, the addition of absorbents may cause secondary pollution. Likewise, there is a similar problem of chemical residues in the chemical precipitation and oxidation techniques. In contrast, biodegradation technologies are often of a low degradation efficiency. In this review, major techniques for the removal of plastic particles and the mechanisms, efficiency, advantages, and disadvantages of these technologies have been discussed.