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Journal of Zhejiang University SCIENCE A
ISSN 1673-565X(Print), 1862-1775(Online), Monthly
2004 Vol.5 No.2 P.180-185
Degradation of chlorophenol by in-situ electrochemically generated oxidant
Abstract: A novel in-situ electrochemical oxidation method was applied to the degradation of wastewater containing chlorophenol. Under oxygen sparging, the strong oxidant, hydrogen dioxide, could be in-situ generated through the reduction of oxygen on the surface of the cathode. The removal rate of chlorophenol could be increased 149% when oxygen was induced in the electrochemical cell. The promotion factor was estimated to be about 82.63% according to the pseudo-first-order reaction rate constant (min-1). Important operating parameters such as current density, sparged oxygen rate were investigated. Higher sparged oxygen rate could improve the degradation of chlorophenol. To make full use of oxygen, however, sparged oxygen rate of 0.05 m3/h was adopted in this work. Oxidation-reduction potential could remarkably affect the generation of hydrogen peroxide. It was found that the removal rate of chlorophenol was not in direct proportion to the applied current density. The optimum current density was 3.5 mA/cm2 when initial chlorophenol concentration was 100 mg/L and sparged oxygen rate was 0.05 m3/h.
Key words: In-situ electrochemical oxidation, Chlorophenol, Oxygen, Hydrogen peroxide
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DOI:
10.1631/jzus.2004.0180
CLC number:
TQ150.9; O646.5; X783
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Received:
2003-02-25
Revision Accepted:
2003-07-04
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