How ion exchange technology is revolutionizing our drinking water

Clean drinking – filtering water with ion exchangers

Drinking water in Germany is of good quality. This is ensured by numerous municipal waterworks. Nevertheless, in some cases it can be useful to have a water filter in the home. If you know how the different water filter systems work and what their characteristics are, you can better decide which water filter is right for your tap water. However, when choosing a water filter, it is also important to consider how the system is operated and how much it costs.

There are four water filter systems that we will briefly introduce in this article: ion exchangers, activated carbon filters, osmosis filters, and distillation systems. Clearly, each of them has advantages and disadvantages. Each filters different types of substances to varying degrees of effectiveness.

The science behind ion exchange filter technology

Ion exchange technology is easy to understand if you know the following: Water filter systems that use ion exchangers rely on the charges in the water. And these depend on the type of particles dissolved in the water. These charged particles are called ions, or more precisely, cations and anions. Cations are positively charged ions that are missing one electron. Anions are particles that have one electron too many and are therefore negatively charged.

Cations include elements such as calcium, potassium, magnesium, but also copper, lead, aluminum, cesium, and cadmium—these are viewed rather critically from a health perspective, for example—and should not be present in drinking water. Anions include iodide, bromide, hydrogen sulfates, or nitrites, nitrates, and phosphates, which are undesirable in water.

The name “ion exchanger” says it all. Due to their physical and chemical properties, ion exchange filters have the ability to remove or, more accurately, exchange dissolved elements in water that occur as charged particles. For example, if calcium with a double positive charge is to be reduced in the water, it is replaced by positively charged sodium from the filter resin. However, it is also possible to use positively charged hydrogen ions to exchange anions for negatively charged hydroxide ions. This allows water filter systems such as ZeroWater to produce pure water with almost no dissolved particles (TDS value/Total Dissolved Solids, total dissolved solids reduced by 99.6%).

Water hardness is also directly dependent on dissolved ionic minerals such as calcium, magnesium, and sulfates. With a water filtration system, you can therefore easily influence the hardness of your drinking water.

What can a water filtration system actually do?

Water filters for tap water are based on different physical-chemical principles. At ZeroWater, we have decided to combine several technologies. Our system consists of a coarse filter, a foam distributor, activated carbon plus oxidation-reduction alloy, ion exchangers, and ultra-fine sieves and flow membranes. Amazingly, packed together compactly, you can't even see this diversity from the outside.

Our 5-stage water filtration system enhances the fundamentally good performance already offered by the ion exchanger. By combining the various filters, ZeroWater filters the same pollutants and contaminants from the water as other tabletop filter systems combined.

99.6% of dissolved particles and substances, including lead and other heavy metals, are reduced. Independent laboratories have tested and proven that ZeroWater also reduces arsenic and radium in water. Also interesting: the water filter also reliably filters out the controversial weed killer glyphosate.

Even though we clearly favor the ion exchanger, every water filtration system has its merits and strengths. Three other effective filtration techniques are as follows:

Activated carbon filter

An activated carbon filter can be thought of as a large sponge. The many pores in the material increase its surface area: this allows larger suspended particles to be retained mechanically, while at the same time the upper contact surface attracts and binds contaminants and pollutants due to charge relationships. This is called ‘adsorption’.

Tap water is freed of unwanted substances as it flows through. These include organic substances such as chlorinated hydrocarbons, pesticides or herbicides, medications, chloride, and basic metals such as zinc, copper, or mercury. Heavy metals, nitrates, or calcium and magnesium cannot be reduced in this way. The filtered pollutants are concentrated in the filter. The activated carbon filter must therefore be replaced regularly with a new one.

Reverse osmosis filter

This water filtration requires a semi-permeable membrane. Tap water is pressed against this thin layer, which is permeable to water but not to dissolved substances. The water molecules can pass through the membrane, while the rest remains behind. The water is cleaned, so to speak, as if through an ultra-fine filter. This leaves bacteria, pollutants such as pesticides, drug residues, but also nitrate, nitrite, and phosphates in the filter. The filtered water has a high degree of purity.

At the same time, the retained residues and pollutants produce highly saturated wastewater that must be disposed of continuously. This is why reverse osmosis filters are rarely used in simple household appliances.

Distillation

Heating water, evaporating it, collecting the steam, and allowing it to cool – that is the basic principle of distillation. This requires a lot of energy and demineralizes the water almost completely. You also don't need to worry about bacteria, germs, or organic contaminants in such water. When used in the medical field, distillation provides 100% safety.

Better than the rest: ion exchange versus other filter systems

According to our evaluation, ion exchange technology offers the best results from numerous tests, studies, and water tastings. The combination of healthy water with good taste and ease of use is unbeatable.

The advantages of ZeroWater tabletop water filters from our point of view:

• Easy to use and efficient in filter performance.
• Improves the taste and smell of the water.
• Maintenance is easy, as the filter cartridge can be cleaned and replaced.
• The maintenance costs of the device are low.
• The exchange resin has a long service life.

On the other hand, the disadvantages are rather minor:

• The entire filter system requires slightly more maintenance than pure activated carbon filters.
• Care must be taken to ensure that no bacterial contamination occurs.

Our conclusion: A ZeroWater filter is the fast and reliable alternative for clean water. The purchase price is much lower than for other water filters with comparable results. It is ready for immediate use without any major installation effort.

Not convinced yet? Try a coffee made with filtered water from ZeroWater – after the first cup, you'll surely change your mind! We, as well as tea sommeliers and tea producers, recommend ZeroWater to achieve an incomparable tea and coffee taste. Write to us: How good does your coffee currently taste and how good does it taste with water from the ZeroWater filter?