Photocatalytic degradation of the insecticide acetamiprid on TiO2 catalyst

The work is concerned with the photocatalytic degradation of acetamiprid, a widely used pyridine-based neonicotinoid insecticide, in UV-irradiated aqueous suspensions of O2/TiO2. The rate of degradation was studied by HPLC/DAD and UV spectrophotometry. It was found that the reaction in the investigated concentration range (0.5-2.0 mg cm-3) is of a pseudo-first order. The ¹H NMR analysis indicated that beside acetaldehyde, formic and acetic acid, pyridine-containing intermediates (e.g. 6-chloronicotinic acid) formed during the process. The HPLC/MS measurements also proved the presence of aromatic degradation intermediates. During the photocatalytic process the pH changed by even three units, from 5 to 2. In contrast to the photocatalytic results in the photolytic experimental conditions, acetamiprid appeared to be stable. To get a deeper insight into the complex photocatalytic process of acetamiprid, the photocatalytic degradation of 6-chloronicotinic acid, the detected pyridine-based degradation product, was also investigated.

Bibliographic Details

Main Authors:	Guzsvány,Valéria J., Csanádi,János J., Lazić,Sanja D., Gaál,Ferenc F.
Format:	Digital revista
Language:	English
Published:	Sociedade Brasileira de Química 2009
Online Access:	http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000100023
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