What are Ion Exchange Resins?
Ion exchange resins can be made from synthetic or natural materials shaped into grain-of-sand-sized beads. Ions are negatively or positively charged atoms or molecules. The ion exchange resins have the opposite charge of the contaminant ions they are treating. This causes contaminants in water pumped through a container of ion exchange resin to be attracted to and stick to the resin similar to the way metal reacts to a magnet. When the contaminant ion attaches to the resin, it displaces another similarly charged ion into the water being treated. That ion is “exchanged” for the contaminant. Ion Exchange Resin Beds (Courtesy of the Purolite Company) Home water-softener systems use ion exchange to draw out the chemicals that make the water hard. The exchange ion in these systems is usually sodium. At Camp Edwards, ion exchange resins will be used to remove perchlorate, a negatively charged ion, from groundwater. The “exchange” ion will be chloride – an ingredient in table salt that is nat
