Preparation of recyclable corn straw fiber as oil absorbent via a one-step direct modification

Abstract Accidental marine oil discharge causes severe environmental pollution and thus remediation is essential. However, the removal and recycling of the spilled oil using economical and highly efficient methods are still major challenges. In this work, an oil absorbent of corn straw fibers (CSF) were prepared via a one-step direct modification with hydrophobic octyltrimethoxylsilane (OTS). With the surface modification, the CSF exhibited both superhydrophobicity and superoleophilicity, and the contact angles of water and oil on the as-prepared samples were 156 ± 1° and 0°, respectively. Owing to the oleophilicity and hydrophobicity features of the CSF, it could be used to selectively absorb oil in water. The adsorption capacity of the as-prepared absorbents for diesel oil, the recyclability, and the reaction mechanism between OTS and the CSF were investigated in detail. The oil absorbent could still remain superhydrophobic even after eleven successive cycles of oil-water separation. With the characteristics of easy biodegradability, durability, and recyclability, as well as the facile procedures involved, oil absorbent of CSF prepared by direct OTS-modification is expected to be used for oil spill cleanup and recovery.