DIAION™ CR11 has iminodiacetic acid group as chelating ligand which is bonded onto a highly porous crosslinked polystyrene matrix. DIAION™ CR11 shows large affinity for alkaline earth and transition metal ions, and the selectivity is similar to that of ethylene diamine tetra-acetic acid (EDTA).

The selectivity order of DIAION™ CR11 for metal ions is as follows:

Cr³⁺ > In³⁺ > Fe³⁺ > Ce³⁺ > Al³⁺ > La³⁺ > Hg²⁺ > UO²⁺ > Cu²⁺ > VO²⁺ > Pb²⁺ > Ni²⁺ > Cd²⁺ > Cd²⁺ > Zn²⁺ > Co²⁺ > Fe²⁺ > Mn²⁺ > Be²⁺ > Ca²⁺ > Mg²⁺ > St²⁺

Adsorbed metal ions can be eluted with an acid, and the resin can be reused after regeneration with caustic alkali.

The most typical application of DIAION™CR11 is the secondary purification of brine in Chlor-soda electrolysis plants. DIAION™ can remove a small number of alkaline earth metals (Ca²⁺, Mg²⁺, St²⁺) from a highly concentrated sodium chloride solution.