Fundamental Study on Recovery of Spilled Oil Using Magnetic Fluid

This study proposes a method for collecting spilled oil by adding magnetic fluid to the spilled oil, mixing them to impart magnetism to the spilled oil, and then collecting the oil using magnetic force. Several types of magnetic fluids composed of fatty‐acid‐modified magnetite nanoparticles and fuel oil A were prepared. The magnetic fluids were used to recover fuel oil A on a beaker scale, and up to 99% of fuel oil A was recovered. Subsequently, repeated experiments were conducted, in which the mixture of the recovered magnetic fluid dispersed in fuel oil A was concentrated again using a stronger magnetic field, and then, fuel oil A was recovered using the concentrated magnetic fluid. Even after the fourth use of the magnetic fluid, more than 90% of fuel oil A was recovered. Finally, fuel oil A recovery experiments were conducted using a drum‐type magnet, and approximately 73% of fuel oil A was recovered. The results demonstrated the feasibility of recovering spilled oil by magnetic seeding using magnetic fluids followed by magnetic separation.