Divalent metal ion removal resin is a macroporous styrene-based ion exchange resin with an iminodiacetic acid as the chelating functional group. Within the solutions where multi-valences of metallic ions exist, it only binds to the metallic ions whose valences are greater than or equal to divalence to form stable complexes. Chelating Resin is mainly used for strong brine softening and electrophoretic refining, particularly being widely applied in removing heavy metallic divalent copper ions within wastewater treatment.