Deionization Deionization Your Partner in Resolving Environmental and Processing Concerns. Deionization is process of removing ionized solids from water using the principles of ion exchange. The softener requires one resin to accomplish its job because it exchanges only cations. The deionizer requires two resins because it exchanges both cations and anions. The simplest deionizer is a two-column unit in which the cation exchange resin is held in one pressure vessel and the anion exchange resin in another.
Water first passes through the cation tank then the anion tank.
When the resin is in the regenerated state, each exchange site is occupied by a positively charged hydrogen ion. As the positively charged cations in the water contact the beads, they are attracted to the negative exchange sites, Since they are stronger in their positive charge than the positive hydrogen ions, they drive off the hydrogen ions and attach to the exchange sites. By so doing, they maintain a balance between positive and negative charges. The positive hydrogen ions attach to negative exchange site on the beads, restoring the resin to its regenerated hydrogen form.