PolyU IR
 

PolyU Institutional Repository >
Civil and Environmental Engineering >
CEE Journal/Magazine Articles >

Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/2430

Title: Photocatalytic degradation of methylparathion - An endocrine disruptor by Bi³⁺-doped TiO₂
Authors: Rengaraj, S.
Li, Xiang-zhong
Tanner, Peter A.
Fan, Z. F.
Pang, Geoffrey Kin-hung
Subjects: Bismuth
Bi³⁺
Endocrine disrupters
Methylparathion
Photocatalytic oxidation
Titanium dioxide
TiO₂
UV
Issue Date: 16-Mar-2006
Publisher: Elsevier
Citation: Journal of molecular catalysis A: Chemical, 16 Mar. 2006, v. 247, no. 1-2, p. 36-43.
Abstract: The relationships between the catalyst physicochemical properties and its photocatalytic activity have been investigated and elucidated in the photodegradation of the organophosphate insecticide methylparathion. The photocatalytic degradation was investigated by using a sol–gel synthesized Bi³⁺-doped TiO₂nanocatalyst (using doping concentrations up to 2 wt.% Bi³⁺) under UV-A light in aqueous suspension. The prepared photocatalysts were characterized by X-ray diffraction, (environmental) scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray analysis, IR–UV–vis absorption spectra, X-ray photoelectron emission spectroscopy and room- and low-temperature photoluminescence spectra. The photodegradation and mineralization products of methylparathion were analyzed by high performance liquid chromatography, dissolved organic carbon and ion chromatography techniques. The experiments demonstrated that the presence of Bi³⁺ in TiO₂catalysts substantially enhances the photocatalytic degradation of methylparathion in aqueous suspension. The degradation of methylparathion by these catalysts followed a first-order kinetic model and an optimal dosage between 0.7 and 1.5% Bi³⁺ in TiO₂achieved the fastest methylparathion degradation under the experimental conditions. This study has also investigated the mineralization of methylparathion in terms of carbon, sulphur and nitrogen conversion during the photocatalytic reaction. The possible mechanisms of photoluminescence quenching and photodegradation are elucidated in the context of donor–acceptor interactions with Bi–O polyhedra acting as electron trapping centres which hinder electron–hole pair recombination.
Description: DOI: 10.1016/j.molcata.2005.11.030
Rights: Journal of Molecular Catalysis A: Chemical © 2005 Elsevier B. V. The journal web site is located at http://www.sciencedirect.com.
Type: Journal/Magazine Article
URI: http://hdl.handle.net/10397/2430
ISSN: 1381-1169
Appears in Collections:CEE Journal/Magazine Articles

Files in This Item:

File Description SizeFormat
59.pdfPre-published version1.31 MBAdobe PDFView/Open
Locate publisher version via PolyU eLinks



Facebook Facebook del.icio.us del.icio.us LinkedIn LinkedIn


All items in the PolyU Institutional Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
No item in the PolyU IR may be reproduced for commercial or resale purposes.

 

© Pao Yue-kong Library, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
Powered by DSpace (Version 1.5.2)  © MIT and HP
Feedback | Privacy Policy Statement | Copyright & Restrictions - Feedback