Utilization of rice husks for the production of oil sorbent materials

Rice is the third largest cultivated cereal crop in the world, making rice hulls one of the most abundant biowastes on Earth. In this manuscript, the rice husks have been subjected to alkali treatment at low temperatures aiming to produce a lignocellulosic sorbent material as well as removing their silica. This absorbent has been subsequently tested for marine diesel spill clean up. Various treatment conditions such as NaOH concentration, duration, and temperature have been investigated. The optimized cellulosic sorbents show high RMG380 marine diesel uptake due to low bulk density and their fluffy structure. It is argued that the bulk density is a critical factor in the excellent uptake capacity. As far as the authors are aware, these results (as high as 20 g of RMG380 sorbed per gram of sobent) show the highest oil sorption for rice husk derived materials reported in literature. Other advantages include higher yields and lower treatment temperatures compared to other studies. The proposed cheap and environmentally friendly method provides a simple and safe technique for the production of valuable products from lignocellulosic agricultural waste.