Keywords: heterogeneous photocatalysis, methomyl, zinc oxide, titanium dioxide, insecticides, photooxidation, sunlight induced degradation, semiconducting oxides, photocatalytic oxidation, wastewater treatment, wastewater reuse, water scarcity
Photocatalytic oxidation of methomyl in the presence of semiconducting oxides
The photocatalytic degradation of methomyl, a broad spectrum carbamate insecticide, has been investigated in aqueous heterogeneous solutions containing semiconductor oxides as photocatalysts. It was observed that, in the presence of the catalysts, quantitative degradation of the organic molecule occurs after four hours of illumination. As mineralisation products, CO2 and SO42− ions have been identified, whereas the nitrogen atom forms NH4+ and NO3− ions. Various commercial catalysts were compared with respect to their overall photocatalytic efficiency, while the initial photonic efficiency (ζ) of mineralisation under various experimental conditions have been calculated.