Modeling Magnetic Configurations for Improved Separations of Magnetic and Non-Magnetic Materials

S. Khushrushahi[1], T.A. Hatton[1], M. Zahn[1]
[1]Massachusetts Institute of Technology, Cambridge, MA, USA

Magnetic separation of magnetic liquid phases/particles from non-magnetic liquid phases/particles are needed for applications such as cleaning up oil spills by separating oil and water liquid phases or separating magnetic materials from non-magnetic materials in biomedical and microfluidic applications. Magnetic fluids (also called ferrofluids), in a magnetic field, experience a magnetic force density. COMSOL Multiphysics was used to show that magnetic energy density of a particular permanent magnet configuration is a more intuitive way of understanding how a magnetic fluid moves in a magnetic field. As a result, a novel magnetic separation technique was developed, using permanent magnet edges and Halbach magnet arrays, that separated a variable magnetic volume fraction from a mixture of magnetic and non-magnetic liquid phases.