The appearance of new refractory and biorecalcitrant pollutants in water, together with the growing need to use renewable energies, have triggered the interest in developing new water treatment systems activated by sunlight. Two of these processes are the so-called photocatalysis, which uses solid catalysts activated by the effect of light, and photo-Fenton, which combines iron salts with hydrogen peroxide. Both aim to completely oxidize, for their removal in the form of carbon dioxide, contaminants that appear in very low concentrations and resist conventional treatments.
IMDEA Energy has participated in a study led by the University of Strasbourg, published as a "Hot Article" in the journal Catalysis Science & Technology, * aimed at developing materials with a dual activity in water treatment combining photocatalysis and photo- Fenton processes. These catalysts, composed of lanthanum-iron oxides doped with titanium, are capable, on the one hand, of being activated by sunlight due to their semiconductor nature and, on the other hand, of catalyzing the oxidizing action of hydrogen peroxide due to their content in iron. As a result, it has been possible to completely eliminate, under the action of UVA light (contained in sunlight by approximately 5%), two model contaminants in water: 4-chlorophenol, representative of refractory contaminants in industrial wastewater, and myclobutanil, one of the most frequently detected pesticides in both surface and groundwater in the Upper Rhine area, in Central Europe.
* P. García-Muñoz, F. Fresno, C. Lefevre, D. Robert, N. Keller, Synergy Effect Between Photocatalysis and Heterogeneous PhotoFenton Catalysis on Ti-Doped LaFeO3 Perovskite for High Efficiency Light-Assisted Water Treatment. Catalysis Science & Technology 10 (2020) 1299, https://doi.org/10.1039/C9CY02269D
More information: Fernando Fresno, Senior Assistant Researcher, Photoactivated Processes Unit. firstname.lastname@example.org