Advanced Synthetic and Bio-Based Sorbents for Oil Spill Clean-up: A Review of Novel Trends

Abstract

Due to immense population growth and economic development, the use of crude oil for various energy applications has escalated in the past few decades. This has led to the large-scale exploitation of oil reserves which has further resulted in the accidental release of large amounts of oil into our oceans. In recent years, significant emphasis has been placed on processes involving oil sorption by various natural and synthetic sorbents. Several sorbent materials based on synthetic polymers such as polypropylene, polyurethane, polystyrene, etc., possessing three-dimensional porous structure, large surface area, high mechanical strength, and exhibiting good oil recoverability and reusability, have been employed for oil-water separation processes. Conversely, many of these materials in their native or pristine form are amphipathic, which prevents their large-scale use in oil spill clean-up. This has led to researchers exploring surface modifications of commercially available sorbent polymeric materials to enhance their oleophilicity and hydrophobicity. This review article summarizes and discusses recent advances in the strategies for the fabrication of newer surface-modified synthetic polymeric materials and natural bio-based sorbents, and further highlights their effectiveness in dealing with the oil/water separation challenges.