Fraunhofer Institute for Surface Engineering and Thin Films IST
Water purification by means of diamond electrodes.
Diamond electrodes for disinfection, antifouling, pollutant removal and pest control
Pollutant control without the addition of chemicals
In many applications, pollutants need to be efficiently reduced or removed - preferably without the addition of chemicals. Examples include reducing the germs in drinking water or on surfaces, decreasing the micro-pollutants in wastewater, preventing biofilms in ultrapure water systems, refrigeration systems or process equipment for beverages or food, or reducing soil pests such as nematodes. All of these applications require strong oxidants such as ozone, hydrogen peroxide, or hydroxyl radicals with which to destroy the contaminants.
Highly efficient cells for electrochemical oxidation with optimally designed diamond electrodes
For the economic deployment of electrochemical oxidation with diamond electrodes, the cells must be optimally adapted to the customer's individual conditions. The Fraunhofer IST is able to develop specific electrode geometries and to coat them with various diamond modifications by means of highly productive coating technology. In addition, customers can rely on our expertise in designing and optimizing the flow conditions and the reaction kinetics of the electrochemical cells for their particular application by means of simulation and modeling.
Design of electrochemical diamond-electrode cells
Take advantage of our extensive experience as one of the pioneers of diamond-coated electrodes as well as our comprehensive expertise in multiscale simulation and benefit from our contacts to cell manufacturers.
Demonstrator systems
Among the common disinfectants, ozone in dissolved form in water enables safe and efficient application, in particular in indoor areas. Ozone dissolved in water rapidly decomposes again and therefore has to be produced on site immediately prior to its utilization. For this purpose, the Fraunhofer IST has developed two mobile demonstrator systems with which the effectiveness of ozonated water can be tested in real applications directly on site.
Mobile DiaDis unit for the production of ozonized water
Ozonized water is produced in an electrochemical process and made available for various applications. In this process, ozone, a strong oxidant, is generated extremely energy-efficiently from the water molecules using diamond electrodes directly in the water. It can be used to reduce fouling on RO membranes and to prevent biofilms in ultrapure water or cooling systems. Alternatively, the system can be used to kill viruses, germs and pests, for example to disinfect surfaces or to improve plant growth.
Mobile ozone generator on the basis of diamond electrodes.
Specifications / technical data
- Medium: deionized water with a conductance < 1µS/cm
- Usable volume: 10 - 100 liters (variable)
- Active substance: ozone (O3) dissolved in deionized water
- O3 concentration: up to 10 mg/l
- Ozone output: 200-250 mg/h dissolved O3 at 20°C
- Dimensions: 1500 x 750 x 1950 mm (W x D x H)
- Weight: 280 kg (empty), 400 kg (operation)
Portable spray system for the disinfection of surfaces
Among the commonly used disinfectants, ozone in dissolved form in water allows safe application, particularly for indoor use. However, ozone dissolved in water quickly decomposes and requires immediate production on site. As a self-sufficient system, the mobile backpack sprayer developed at the IST enables the production of a disinfectant agent without the use of additional chemicals. Through the integration of diamond electrodes, the ozone is generated quickly and efficiently directly in the water and can thus ensure the sustainable disinfection of surfaces.
Portable spray unit for the generation of ozonated water for the disinfection of surfaces.
Specifications / technical data
- Backbone: REB 15 PC3, Birchmeier Sprühtechnik AG
- Medium: city water (via ion exchanger); deionized water with conductance < 5 µS/cm
- Usable volume: up to 15 l; approx. 2 l/h
- Active substance: Ozone (O3) dissolved in deionized water
- O3 concentration: up to 1 mg/l dissolved O3 at 20°C
- Weight: 5 kg (empty), 28 kg (operation)