Degradation of metsulfuron methyl by heterogeneous photocatalysis on TiO2 in aqueous suspensions: Kinetic and analytical studies

Elucidation of oxidized products of Chloridazon in advanced oxidation processes using a liquid chromatography/negative electrospray ionization tandem mass spectrometric technique

“…All these products were also observed by excitation of hydrogen peroxide at 254 nm in the presence of CHL under the conditions in which light is mainly absorbed by H 2 O 2 . As largely reported in the literature, the two used experimental conditions are well known to efficiently produce hydroxyl radicals which are more likely the precursor species that permit the formation of the observed by‐products, namely hydroxyl radicals . This was confirmed by the inhibition of CHL degradation when the irradiation was performed in the presence of 2‐propanol used as hydroxyl radical scavenger …”

“…One branch of AOPs that has attracted much attention is the heterogeneous photocatalysis, mainly due to its promising applications in several fields such as photocatalytic water splitting, solar energy conversion, photocatalytic degradation of organic pollutants from waters and disinfection . Heterogeneous photocatalysis using TiO 2 as semiconductor is the most studied method for the oxidation of organic pollutants . The UV excitation of TiO 2 permits the promotion of electrons from the valence band to the conduction band.…”

Analytical Methods for Performing Pesticide Degradation Studies in Environmental Samples

“…The degradation of pesticides occurred after 3 to 5 hours of solar irradiation, while the degradation by UV radiation required 10 hours. Rafqah et al, 2005, investigated the rate of degradation of sulfuron methyl by a photocatalytic process in the presence of two different titanium dioxides, Degussa P 25 and Millennium PC 500 . The times necessary for the disappearance of the pesticide in the presence of Degussa P 25 and Millennium PC 500 were 20 and 80 minutes, respectively, the efficiency of TiO 2 (P 25 ) being the greater.…”

Use of quadrupole time of flight mass spectrometry for the characterization of transformation products of the antibiotic sulfamethazine upon photocatalysis with Pd‐doped ceria‐ZnO nanocomposite

“…In order to achieve the efficient and complete disappearance of the contaminants, photochemical methods such as advanced oxidation processes, mainly based on hydroxyl radical production, were developed . Because this radical is a highly oxidant species, the mineralization of the contaminated solutions may also occur but with much slower rates . Therefore, the generated by‐products may accumulate in the solution, and their elucidation is of great concern because they may show a more toxic behavior when compared with the parent compound.…”