The Photocatalytic Oxidation of 4-Chlorophenol Using Bi₂WO₆ under Solar Light Irradiation

Abstract

This report discusses the effects of the initial concentration of 4-chlorophenol (4-CP) on its solar light photoinduced oxidation/mineralization kinetics on Bi2WO6catalyst. Photocatalytic degradation followed the Langmuir-Hinshelwood (L-H) mechanism. From the kinetic data the Langmuir adsorption equilibrium constant of 4-CP on the Bi2WO6surface and the L-H maximum reaction rate for 4-CP oxidation have been evaluated. Chromatographic and spectroscopy studies show the presence ofp-benzoquinone and maleic acid as the main reaction products; these compounds first increase and then decay until they disappear. Chemical oxygen demand (COD) and produced CO2measurement show that photocatalytic mineralization of the phenolic compound was readily possible in a wide concentration range.

High-Field Growth of Semiconducting Anodic Oxide Films on Metal Surfaces for Photocatalytic Application

“…According to the discussion above, the factors to consider for the synthesis of nanostructured films are (i) a high-field anodization protocol with a valve metal or an alloy of these metals, (ii) a potential-time program for anodization, (iii) an electrolyte containing fluorides, and (iv) the effects of a native passive film and pretreatment of the metal surface. Currently, self-assembled nanotube films of several semiconductors such as TiO 2 , WO 3 [22,50].…”