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Referenztyp Zeitschriften
DOI / URL Link
Titel (primär) Photodegradation of malachite green and malachite green carbinol under irradiation with different wavelength ranges
Autor Fischer, A.R.; Werner, P.; Goss, K.-U.;
Journal / Serie Chemosphere
Erscheinungsjahr 2011
Department AUC;
Band/Volume 82
Heft 2
Sprache englisch;
Keywords Malachite green; Photodegradation; Photocatalyst; Quantum yields; Wavelength ranges
Abstract The dye malachite green (MG) is used worldwide as a fungicide in aquaculture. It is a toxic substance which in aqueous solutions is partly converted into its non-ionic colorless form (leucocarbinol). The equilibrium between these two forms is pH-dependent (pK = 6.9). To assess the photodegradation of MG under sunlight conditions, both species were irradiated separately in aqueous solutions with different pH values (4.0 and 12.0) using various ultraviolet and visible wavelength ranges (UV/VIS). A 700 W high-pressure mercury lamp with special filters was used. No artificial photooxidizers such as H2O2 or TiO2 were added. MG leucocarbinol proved to be much more sensitive to irradiation than the dye form. Quantum yields F were calculated for some wavelength ranges as follows: MG carbinol: F(280-312nm) is 4.3 × 10-3, F(313-410nm) is 5.8 × 10-3, and MG dye: F(280-312nm) is 4.8 × 10-5, F(313-365nm) is 1.1 × 10-5, and F(>365nm) is 0, respectively. Therefore, the solar photolysis of MG is an important sink and primarily depends on the photodegradation of the colorless leucocarbinol. During the irradiation of MG leucocarbinol with wavelengths >365 nm, an intermediate was formed which has photocatalytical properties.
ID 10745
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=10745
Fischer, A.R., Werner, P., Goss, K.-U. (2011):
Photodegradation of malachite green and malachite green carbinol under irradiation with different wavelength ranges
Chemosphere 82 (2), 210 - 214