Household

Removal of Hardness from Potable Water

The Lewatit® products applied in drinking water are mainly strong acidic cation exchangers (SAC) and weak acidic cation exchangers (WAC, Picture). SAC products are predominantly used in house installations (PoE systems – point of entry) to efficiently remove all divalent cations (total hardness removal). This process with our product Lewatit® S 1567 or the sustainable alternative Lewatit® S 1567 Scopeblue, is also known as complete softening: glasses and dishes that come out of the dishwasher sparkling clean without a cloudy appearance: laundry is softer and cleaner; there is less detergent required when doing laundry or cleaning dishes. A big benefit is that you will find no hard water deposits on the tub, toilet, appliances and fixtures. So the SAC products prevent hardness precipitation that blocks the water pipes in your household and extends the life expectancy of your appliances and water piping systems. The strong acidic cation exchangers have to be periodically regenerated with a sodium chloride solution (NaCl).

Governments are focusing on providing safe and clean drink­ ing water, investing in infrastructure in order to cope with im­ proving quality. There is an upsurge in demand for purifying systems across households, restaurants, and other estab­ lishments directly at its point of use (PoU systems) providing both an additional barrier of protection against contaminant intrusion as well as achieving higher­quality taste.

With Lewatit® ion exchange resins, we offer a wide range of weak acidic cation exchange products suitable for dealkalization (partial softening) of potable water in PoU systems (cartridge filter applications). Calcium and magnesium can be removed and also ions that are harmful to human health such as lead and copper, releasing other safe ions into the water instead. Outstanding German product quality, long­established technical experience, pro­ duction know­how covering more than 80 years, compliance with a great number of regulatory requirements globally, and drinking water certification are only a few of the characteris­ tics found with the Lewatit® products. With our sustainably produced Lewatit® Scopeblue ion exchange resins, we offer products that have a carbon footprint that is up to 67 percent smaller than products manufactured from conventional fossil sources. Click here for more information.

Depending on the quality of the drinking water, post­treat­ ment may make sense for a variety of reasons. Water hard­ ness is defined as the sum of all alkaline earth ions, referred to as hardness components, whereby calcium represents the greatest problem. In conjunction with carbonate it forms calcium carbonate, i.e., lime, which frequently crystallizes out as a white deposit and can result in scale formation in pipes and on fittings and heat-transfer surfaces (heating, dishwashers, and washing machines, etc.) and, ultimately, damage to household installations and appliances. After all, coffee and tea taste significantly better when they are made using water with a low lime content. The complete softening is a process, where strong acidic cation exchange resins are being used.

Weak Acidic Cation Exchange Resins

Strong Acidic Cation Exchange Resins

Check out full information in Brochure Lewatit Product Guide 2025