Energy-efficient advanced oxidation for removal of organic substances in wastewater through Plasmonically Enhanced Photocatalysis

The aim of the PEPcat project is to develop an energy- and resource-efficient process for the post-treatment of conventional wastewater treatment plant effluents that not only reduces the ecotoxicological and human toxicity potential, but also enables the reuse of water. The oxidative wastewater treatment developed in this project is based on the generation of highly reactive hydroxyl radicals directly in the water, which can be used to destroy environmentally relevant wastewater constituents. These are much more reactive than chlorine, for example, and are also consumed in fractions of a second, so that, unlike other processes, no chemicals remain in the water. The generation of these hydroxyl radicals with high-energy UV light using titanium dioxide as a catalyst is already the subject of numerous research projects. The innovative approach is to combine this process with the so-called plasmonic effect, which makes it possible to achieve the catalytic effect of the titanium dioxide with visible light as well, so that, for example, the sun can be used as a light source or, if artificial irradiation sources are used, significantly higher efficiency can be achieved by exploiting a higher wavelength range.

For process optimization on a laboratory scale and subsequent plant development and construction, the following work steps will take place at the beginning of the project in Germany:

• Investigation of the purification performance for organic carbon compounds.
• Development of process understanding through extensive investigations of various influencing factors.

• Optimization of the catalyst and the reactor geometry.

After the development of a nanostructured coating for plasmonic enhanced photocatalysis, an up-scaling of the technology to industrial production will take place.

In the further course of the project, the pilot plant developed in Germany will be integrated at the Dongba wastewater treatment plant in China.