37 research outputs found
Formation of hydroxyl radicals by irradiated 1-nitronaphthalene (1NN): oxidation of hydroxyl ions and water by the 1NN triplet state
PHOTOTRANSFORMATION DE POLLUANTS AROMATIQUES DANS L'EAU INFLUENCE DE LA MATIERE ORGANIQUE NATURELLE EVALUATION DE LA PHOTODEGRADABILITE EN LUMIERE SOLAIRE
CLERMONT FD-BCIU Sci.et Tech. (630142101) / SudocSudocFranceF
Photochemical Transformation of Acifluorfen under Laboratory and Natural Conditions.
Abstract not availableJRC.I-Institute for Health and Consumer Protection (Ispra
Mechanism of the Photochemical Transformation of Naphtalene in Water.
Abstract not availableJRC.I-Institute for Health and Consumer Protection (Ispra
Phototransformation of 4-Chloro-2-Methylphenol in Water: Influence of Humic Substances on the Reactions.
The phototransformation of 4-chloro-2-methylphenol was studied using distilled water, solutions of humic substances and natural waters. Samples were irradiated at 280 nm, with polychromatic lamps emitting within the wavelenght ranges 290-350 and 300-450 nm or exposed to sunlight. The photolysis of 4-chloro-2-methylphenol at 280 nm in pure aerated water leads to methylbenzoquinone as the main primary photoproduct; the quantum yield of the direct photolysis is equal to 0.66. When 4-chloro-2-methylphenol is irradiated alone by polychromatic light or exposed to solar-light, methylhydroquinone and methylhydroxybenzoquinone are found as main photoproducts because secondary photolysis of methylbenzoquinone occurs. Humic substances enhance the rate of photodegradation of 4-chloro-2-methylphenol at lambda > 300nm. In these conditions, 4-chloro-2-methylphenol is transformed into methylhydroquinone, methylhydroxybenzoquinone essentially via direct photolysis and into 3-chloro-trans-trans and cis-trans-1-methyl-1-one-2, 4-hexadienoic acids through photoinduced reactions. These four photoproducts are found when 4-chloro-2-methylphenol is irradiated in natural waters at lambda > 300 nm. The phototransformation of 4-chloro-2-methylphenol under environmental conditions occurs therefore through both direct and humic substances-photoinduced processes.JRC.(EI)-Environment Institut