Improvement of Li/Mg monovalent ion selectivity of cation-exchange membranes by incorporation of cerium or zirconium phosphate particles

To improve the selectivity of cation-exchange membranes to the transfer of lithium with respect to magnesium during the electrodialysis desalination of lithium and magnesium sulfates solutions, the surface of a commercial cation-exchange membrane based on sulfated polystyrene was modified with cerium(III, IV) and zirconium phosphates. Upon incorporation of phosphate particles, the Li/Mg selectivity coefficients of the membranes increased up to 113%.