Ion exchange is a water treatment process that involves the removal of dissolved ions from water through a reversible chemical reaction. It utilises a resin material with charged sites that attract and exchange ions in the water with ions of similar charge that are bound to the resin.
In water treatment, ion exchange is often used for the removal of harmful contaminants such as heavy metals (e.g., lead, mercury), hardness ions (e.g., calcium, magnesium), and certain dissolved salts (e.g., nitrate, sulfate). The process typically involves passing water through a column filled with resin beads. As the water flows through the column, the ions in the water bind to the charged sites on the resin beads, displacing ions of similar charge that were previously bound to the resin.
