Bio-based multifunctional carbon aerogels from sugarcane residue for organic solvents adsorption and solar-thermal-driven oil removal

Abstract With the population increasing and industrialization developing, the high demand for clean water has become a major issue that should be meet. In particular, leak of oils and organic solvents, discharge of wastewater put greater pressure on water resource. Hence, the effective and environment-friendly treatment method for the wastewater has received much attention in international society. The carbon aerogels obtained from high-temperature carbonized treatment (C-cane) without chemical modification were regarded as effective monolithic hydrophobic/oleophilic oil-absorber in our work. Benefitting from the graphitization and aromatization reaction during carbonization process, the prepared sugarcane-based carbon aerogel obtained desirable hydrophobicity and oleophilicity. On this account, high absorption capacity for organic solvents (17.1 g/g–37.7 g/g) can be reached easily. Moreover, the C-cane can be used in emulsion separation. Due to the super resistance to fire, sugarcane-based carbon aerogel also presents good reusability. Meanwhile, the excellent photo-thermal conversion capability obtained during carbonization promote the adsorption of high viscous oil into sugarcane-based aerogel, presenting the solar-assisted oil absorption capability ranged from 31.9 g/g to 55.02 g/g. Outstanding light captive and photothermal conversion performance also enable them to be competent for rapidly separating high viscosity oil from water. The work convert agricultural residue into a highly-efficient adsorbing material, offering a commercially-available and scalable approach to solve the leakage of organic solvents and oil.