Dry separation of fine mineral grains

If mineral suites are immersed in a paramagnetic fluid in a magnetic field with high field gradient, the additional buoyancy effects generated within the fluid may cause mineral separation as different components float at different heights according to their density. This is known as magneto-Archimedes flotation and was pioneered by Rosenweig (1968). Recently, superconducting magnets have been developed with greater field strengths and gradients than previously possible. Recent studies at the University of Nottingham have shown that liquid oxygen has the ability to float gold (Catherall et al., 2003b). This study examines the potential of these systems to float and therefore separate common minerals, using manganese chloride solution at room temperature and cryogenic oxygen.