Microplastic pollutants in water: A comprehensive review on their remediation by adsorption using various adsorbents

Microplastics (MPs), as emerging pollutants, have attracted the attention of environmentalists, statespersons, and the scientific community over the last few decades. To address the spread of MPs in the environment, it is imperative to develop various removal techniques and materials that are effective, scalable, and ecologically benign. However, to the best of our knowledge, no review has systematically examined the removal of MPs using adsorption or provided an in-depth discussion on various adsorbents. Adsorption is an inexpensive and effective technology for wastewater treatment. Recently, many researchers have conducted studies on MP remediation using diverse adsorbent materials, such as biochar, activated carbon, sponges, carbon nanotubes, metal-layered oxides, metal-organic frameworks (MOFs), and zeolites. Each adsorbent has advantages and disadvantages. To overcome their disadvantages, researchers have been designing and developing hybrid adsorbents for MP remediation. This review provides insights into these individual adsorbents and also discusses hybrid adsorbents for MP removal. Finally, the review elaborates on future possibilities and ways to enable more efficient, scalable, and environmentally friendly MP cleanup. Overall, this review bridges the gap between contemporary MP remediation using adsorption techniques and adsorbent development.