Dual bed vs. mixed bed?

Deionizers require using at least two types of ion exchange resins to produce deionized water. One resin will remove positively charged ions and the other will remove negatively charged ions. In a dual bed system, the cation resin is always first and the anion resin is always second. A dual bed system is typically used when higher quantities of water are needed.

Mixed bed resin is a mix of both cation and anion resin. The cation resin will attract positively charged ions, such as calcium, sodium, magnesium, iron, manganese and potassium. The anion resin will remove negatively charged ions, such as sulfates, chlorides, carbonates, bicarbonates, nitrates and silica. Mixed bed resin is typically used in medical applications, research facilities, laboratories, biotech manufacturing, pharmaceutical and electronics when a higher quality of DI is required.