Ion exchange resin

Description

A synthetic polymer or modified zeolite that has the capacity to reversibly substitute cations or anions with salts in aqueous solutions. For example, cation exchange resins contain reactive anionic end groups (sulfonic, carboxylic, phosphonic acid, phenolic, etc.) that have a loosely bound cation, such as a hydrogen or sodium ion. In an aqueous solution this loosely bound cation will exchange places with a more reactive cation, such as calcium or magnesium ions in hard water. Ion exchange resins are used for purification of chemicals, softening of water, recovery of trace metals, removal of salts and for chromatographic analysis.

Synonyms and Related Terms

ion exchanger; Ionenaustauscher (Deut.); échangeur d'ions (Fr.); permutador iónico (Port.)