Understanding Ion Exchange Resins:
A Beginner's Guide

If you’ve ever wondered how the science behind water purification works, read this article to find out! We’re going to explore what resins are, how they work, and why they’re so important. However, if you are simply looking to buy some premium quality Ion Exchange Resin, visit this link. If you would like to know more, read on!

What Are
Ion Exchange Resins?

Ion exchange resins are small, highly porous beads typically made from an organic polymer substrate. These beads have a unique capability: they can exchange certain ions within a liquid without changing their own structure. This makes them incredibly useful for removing unwanted minerals and ions from liquids, such as purifying water.

Mixed-Bed Ion Exchange Resin becoming saturated by water. Photographed at x2.5 magnification by Andy Byrne.

Resin beads are tiny!

Move the slider and see for yourself!

ionic resin close up magnified photographing resin up close magnified

Mixed-Bed Ion Exchange Resin. Photographed at x10 magnification by Andy Byrne.

How do
Ion Exchange Resins work?

The magic of ion exchange resins lies in their ability to swap out one type of ion for another. Imagine you have water that contains calcium ions, which you want to remove because they can cause hardness. Check out this handy Water Hardness Map to check the water hardness of your area. A common ion exchange resin can replace those calcium ions with sodium ions. The process involves passing the water through a column filled with resin beads. As water contacts the beads, the unwanted ions are captured, and in their place, ions from the resin are released into the water.

This swapping ability comes from the resin’s surface, which is covered with active sites that hold exchangeable ions. These sites are chemically tailored to preferentially bind certain ions over others.

Mixed-Bed Ion Exchange Resin becoming saturated by water. Photographed at x2.5 magnification by Andy Byrne.

Types of
Ion Exchange Resins

There are two main types of ion exchange resins:


  1. Cation Exchange Resins: These have negatively charged active sites that attract and hold positively charged ions (cations) like calcium, magnesium, and sodium.

  2. Anion Exchange Resins: Conversely, these resins have positively charged active sites that capture negatively charged ions (anions) like chloride, sulfate, and nitrate.


Then you have a mixture of both! We call this Mixed-Bed Resin, and it’s particularly useful for window cleaners!

Where Are
Ion Exchange Resins

There are many uses for Ion Exchange Resins. As you can imagine, industrial water purification systems require vast amounts of Mixed-Bed Resin – as we hold so much stock of resin, these large industrial water purification centres often come to Ionic for their resin supply. Yet, resin is used in many other industries, such as; chemical purification, metal refinery and medicines, to name a few.

But, as window cleaners we are most interested in how ion exchange resin is beneficial for us. Most modern window cleaners will be using the Reach & Wash©️ system, requiring hundreds of litres of pure water per day. They need a high quality ion exchange resin capable of producing high levels of purity for as long as possible. We – along with much of the UK window cleaning market – believe that our brand of specially selected premium Ion Exchange Resin fits this bill perfectly. We also believe in keeping our prices as low as possible, to maximise the benefit for our customers and long term partners.


Ion exchange resins are fascinating and vital components of the window cleaning water purification process. Their ability to selectively remove and replace ions makes them indispensable to the modern window cleaner. If you would like to know more about water purification or about how to become a window cleaner, give us a call on 01793 871 386 or email us at info@ionicsystems.com