Photocatalytic degradation of the fungicide Fenhexamid in aqueous TiO(2) suspensions: Identification of intermediates products and reaction pathways
Φόρτωση...
Ημερομηνία
Συγγραφείς
Lambropoulou, D. A.
Konstantinou, I. K.
Albanis, T. A.
Fernandez-Alba, A. R.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Chemosphere
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Liquid-chromatography interfaced with time-of-flight mass spectrometry (LC-TOF/MS) was used to separate and characterize the transformation products arising from TiO(2)-photocatalytic degradation of the fungicide Fenhexamid (FEX) in aqueous solution under simulated solar irradiation. Prior to identification, irradiated solutions of FEX (10 mg L(-1)) were concentrated by solid-phase extraction. Assignments of the mass spectra ions were aided by elemental composition calculations, comparison of structural analogues and available literature, and acquired knowledge regarding mass spectrometry of related heterocyclic compounds. The primary transformation intermediates identified were hydroxyl and/or keto-derivatives. Several positional isomers are typically produced as a consequence of the non-selectivity of the OH radical attack. Moreover, products resulted from the cleavage of the amide and NH- dichlorophenol bonds were formed. Finally, cyclic - benzo[d]oxazole intermediates are also formed through an intramolecular photocyclization process and cleavage of halogen - carbon bond. In the case of the hydroxy and/or keto-derivatives, the generic fragmentation scheme obtained from the interpretation of the ESI-TOF-MS data cannot be diagnostic to precisely localize the position of the entering substituent on the FEX molecule, and thus to characterize all its possible oxygenated derivatives by assigning a plausible structure with confidence. On the basis of identified products different pathways of photocatalytic degradation of FEX were proposed and discussed. (c) 2010 Elsevier Ltd. All rights reserved.
Περιγραφή
Λέξεις-κλειδιά
fenhexamid, lc-tof/ms, pesticides, photocatalysis, tio(2), transformation products, selective photooxidation, mass-spectrometry, titanium-dioxide, cyclohexane, diclofenac, mechanism, liquid, water, photodegradation, transformation
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000289184100020
http://ac.els-cdn.com/S0045653510013962/1-s2.0-S0045653510013962-main.pdf?_tid=3cf203c59b91d52fee9f722af73c393a&acdnat=1333023181_3ec7b433e5cd1c608ee1bfd780bdfaf2
http://ac.els-cdn.com/S0045653510013962/1-s2.0-S0045653510013962-main.pdf?_tid=3cf203c59b91d52fee9f722af73c393a&acdnat=1333023181_3ec7b433e5cd1c608ee1bfd780bdfaf2
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας