Access to clean water is essential for life, yet even in wealthy countries, harmful pollutants are slipping into the water cycle.
Everyday substances like pesticides, drug residues, industrial chemicals, dyes, microplastics, and “forever chemicals” (PFAS) have been found in groundwater, rivers, and even drinking water.
A report from Germany’s Environment Agency showed that by 2023, 40 different pharmaceutical ingredients had already been detected in drinking water alone, with even higher levels in untreated water sources.
Current treatment plants do a lot to clean water, but they often struggle to remove these persistent trace pollutants.
A team at the Fraunhofer Institute for Ceramic Technologies and Systems (IKTS) in Dresden is now tackling this problem with an innovative approach.
They have created compact treatment systems that use special ceramic foams coated with catalysts.
When exposed to ultraviolet (UV) light, these coatings trigger a process called photocatalytic oxidation.
This produces highly reactive particles, known as radicals, that break down pollutants directly in the water.
Unlike other treatment methods, this process doesn’t require extra chemicals like ozone and doesn’t create harmful by-products.
The heart of this system is the foam ceramic itself. It has a sponge-like structure with up to 90 percent open space, which lets light through and provides a large surface area for catalysts to attach.
This design makes it easier for pollutants, catalysts, and light to interact, speeding up the breakdown of unwanted substances. The catalysts are stabilized on the foam so they stay in place and don’t wash away with the water.
Researchers are also designing the entire water treatment units themselves. That means developing not only the foam and coatings but also the UV light sources, reactor designs, and system layouts.
Energy-efficient UV LEDs are being tested to keep power costs low. The units can be customized for different industries and can even be connected to existing treatment plants.
Pilot projects have already shown strong results. In industries such as pharmaceuticals, semiconductors, textiles, and dairy, the ceramic foam systems are proving effective in reducing pollutants before wastewater leaves the factory.
This prevents dangerous substances from entering rivers and groundwater in the first place.
The research team is now working on making the process even more efficient by testing new catalyst designs and combining the ceramic foams with adsorption materials. The long-term goal is to scale up the technology so it can become a standard tool in industrial water cycles.
If successful, these light-powered ceramic systems could play a key role in protecting ecosystems, keeping water supplies safe, and ensuring that future generations have access to clean, high-quality water.