Iodosulfuron degradation by TiO2 photocatalysis: Kinetic and reactional pathway investigations
| Autor: | Mohamad Sleiman, Corinne Ferronato, Pierre Conchon, Jean-Marc Chovelon |
|---|---|
| Přispěvatelé: | Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC) |
| Rok vydání: | 2007 |
| Předmět: |
Identification
Radical Kinetics 02 engineering and technology 010402 general chemistry Photochemistry 01 natural sciences Catalysis Hydroxylation chemistry.chemical_compound Sulfonylurea Structural isomer TiO2 Organic chemistry Photocatalysis Photocatalytic degradation General Environmental Science Aqueous solution Process Chemistry and Technology HPLC–NMR [CHIM.CATA]Chemical Sciences/Catalysis 021001 nanoscience & nanotechnology HPLC–MS 0104 chemical sciences Light intensity Iodosulfuron chemistry Proton NMR 0210 nano-technology |
| Zdroj: | Applied Catalysis B: Environmental Applied Catalysis B: Environmental, Elsevier, 2007, 71, pp.279-290. ⟨10.1016/j.apcatb.2006.09.012⟩ |
| ISSN: | 0926-3373 |
| DOI: | 10.1016/j.apcatb.2006.09.012 |
| Popis: | International audience; The photocatalytic degradation of a sulfonylurea herbicide, iodosulfuron methyl ester (IOME), has been studied in TiO2 aqueous suspensions under UV irradiation. The influence of various parameters such as initial concentration, TiO2 concentration and light intensity on the kinetic process was investigated. Disappearance rate of iodosulfuron followed pseudo-first order kinetics. A special attention was devoted to the identification of intermediates, using a new analytical approach which consists of coupling HPLC–DAD (UV), HPLC–ESI-MS and HPLC–1H NMR techniques after a SPE pre-concentration step. By combining UV, MS and NMR data, up to 20 degradation products were unambiguously identified. Furthermore, 1H NMR data allowed the differentiation of several positional isomers, in particular those of hydroxylation resulting from the attack of OH radicals on the benzene ring of IOME. Kinetic evolution profiles of main intermediates, end products (NO3-, NH4 +, SO4 2-) and total organic carbon (TOC) were also examined in detail. From obtained kinetic and analytical results, the presence of privileged sites for the attack of OH radicals was shown and a detailed degradation pathway was proposed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect