Ion exchange resin how does it work

Treating water is a process that involves removing various types of contaminants from the water that your home is using or your industrial plant requires. One such treatment involves the use of an ion exchange system.

This process is also commonly used to remove additional contaminants from water via processes like disinfection and deionization. The ion exchange chemical process works by removing dissolved ionic contaminants from the water. Water softeners are very similar to ion exchange systems since both systems can remove magnesium and calcium ions from the water. However, ion exchange systems tend to be more comprehensive and are able to get rid of additional contaminants as well.

Anions are negatively charged ions, while cations are positively charged ions. The ion exchange process will take place between a liquid and a solid. While the liquid is always water, the solid can be either zeolite or a resin material. Keep in mind that resin materials can only be charged for a specific period of time. When ions are no longer able to be exchanged, the resin will need to be recharged. Resins can be properly recharged with hydrochloric acid or sodium chloride.

During the cation exchange process, any positively charged ions that touch the resin will be exchanged with other positively charged ions that are found on the surface of the resin. These ions will usually be sodium ions. As for the anion exchange process, the same type of swap will occur, which will result in healthier negatively charged ions being placed in the water. Contaminants like fluoride and nitrate are replaced with chloride. This article provides you with a comprehensive view of ion exchange systems and how they operate.

Dissolved ionic contaminants are removed from water via a simple ion exchange process. This exchange process requires a liquid and a solid, the latter of which can either be a resin material or zeolite.

The larger the ion or the greater its valency, the greater an affinity the ion will have with oppositely charged ions. In a water softening system that uses ion exchange processes, the softening mechanism in question is a cation exchange resin, in which sulfonate anion functional groups are attached to the ion exchange resin matrix.

A counterion solution that features sodium cations gets applied to the resin. The sodium cations are then held to the sulfonate anions through electrostatic attraction, which results in there being a balanced, neutral charge in the resin. The sulfonate functional groups have a greater affinity for hardness cations than sodium cations, which means the hardness ions will displace those sodium cations, which then come out of the ion exchange unit.

This is a fairly technical overview of ion exchange, but it should give you a general idea of how the process works. To learn more about the use of ion exchange resin and how often you need to replace it, contact the team at M. These functional groups are what give the IX resin its separation capabilities, and will vary significantly from one type of resin to the next.

The most common compositions include:. To fully understand how IX resins work, it is important to first understand the principles of the ion exchange reaction.

Put simply, ion exchange is a reversible interchange of charged particles—or ions—with those of like charge. This occurs when ions present on an insoluble IX resin matrix effectively swap places with ions of a similar charge that are present in a surrounding solution. The IX resin functions this way because of its functional groups, which are essentially fixed ions that are permanently bound within the polymer matrix of the resin.

These charged ions will readily bond with ions of an opposing charge, which are delivered through the application of a counterion solution. These counterions will continue to bond with the functional groups until equilibrium is reached.

During an IX cycle, the solution to be treated would be added to the IX resin bed and allowed to flow through the beads. As the solution moves through the IX resin, the functional groups of the resin attract any counterions present in the solution. If the functional groups have a greater affinity for the new counterions than those already present, then the ions in solution will dislodge the existing ions and take their place, bonding with the functional groups through shared electrostatic attraction.

In this example, the softening mechanism consists of a cation exchange resin where sulphonate anion SO 3 — functional groups are fixed to the IX resin matrix. Over time, contaminant ions bind with all available exchange sites in the IX resin.