Rare-earth separations enhanced by magnetic field

The separation of rare earth (RE) elements is a challenge from their discovery to the present day, due to the chemical and physical similarities as a group. The intrinsic properties of REs are basic for separation mechanisms. Due to the large difference in magnetic moment, a new method of selected crystallization enhanced by magnetic field was developed to separate REs efficiently, at room temperature and pressure without complex equipment. An experimental proof of concept is provided for the binary systems RE2(SO4)3-Lu2(SO4)3 (RE = Gd, Nd, Tb, Dy or Ho). This magnetic separation process increases the separation factors of Gd(III)/Lu(III) from their mixture by 39% in kinetics, but similar in or near thermodynamic equilibrium without magnetic field. The βRE/Lu (RE = Gd, Nd, Tb, Dy or Ho) were promoted by 17%-47% with permanent magnet, increasing with raising of the applied magnetic field strength. A process based on magnetic moment difference is a potential alternative method for rare-earth separations, with low energy consumption and high efficiency in the presence of an external magnetic field.