Oil spill cleanup using industrial and agricultural waste-based magnetic silica sorbent material: a green approach

Recent oil spills causing pollution in oceans and other bodies of water require sorbents that are both cost-effective and eco-friendly. Novel magnetic silica sorbent materials (MSS) have been synthesized using ash from rice husks or sugarcane bagasse and red dust, a waste generated in the steel industry. The designed MSS exhibited a definite response to external magnetic fields. The MSS, based on rice husk ash and bagasse ash, showed oil loading capacities of 1.93 and 2.09 times their weight, respectively, and also exhibited recyclability. The MSS were also functionalized to make them oleophilic and hydrophobic using sodium oleate. These functionalized rice husk ash and bagasse ash-based MSS showed oil loading capacities of 3.22 and 2.69 times their weight, respectively. Magnetic separation provided a convenient method for the removal of magnetizable particles by applying an appropriate external magnetic field. The MSS at the end of their utilization cycles were successfully incorporated into geopolymeric material, enabling the process to be zero waste and to achieve the overall goal of finding a green approach to use these wastes after oil spillage cleanup.