Carbon materials as oil sorbents: a review on the synthesis and performance

Oil spill accidents have urged scientists across the world to develop an immediate cleanup technology because the spilled oil significantly affects the ecological and environmental system. Superhydrophobic and superoleophilic materials have shown potential application in the field of oil spill cleanup due to their outstanding absorption capabilities, high selectivity, chemical inertness and excellent recyclability. In this regard, carbon-based absorbents have been considered to be the best candidates as they possess high surface area, low density, excellent mechanical properties, good chemical stability, environmental friendliness and large pore volume. Carbon aerogels, graphene or carbon nanotubes (CNTs) coated sponges, carbon nanotube forests, graphene foams or sponges, carbon coatings, activated carbon, porous carbon nanoparticles and carbon fibers have been widely investigated for water filtration, water/oil separation, oil-spill cleanup, wastewater treatment, gas separation and purification. In this paper, the synthesis, applications and reusability of these carbon-based absorbents have been reviewed and their performances compared.