Anion exchange is a process used to remove dissolved anions (negatively charged ions) from water or other liquids. This method relies on the interaction between charged anions in the liquid and functional groups on a solid exchange resin. During the exchange process, unwanted anions are captured by the resin matrix, while other anions, such as hydroxide, are simultaneously released from the resin.
Similarly, a cation exchanger removes dissolved cations (positively charged ions) from water or other liquids.