Abstract: The photocatalytic degradation of 2,4-dichlorophenol was carried out using un-doped and nitrogen-doped bismuth oxide as catalysts under visible-light irradiation. The results indicated that the nitrogen-doped bismuth oxide exhibited a higher photocatalytic activity than that of the un-doped bismuth oxide. When 2.0 g/L of nitrogen-doped bismuth oxide was added to 20 mg/L of 2,4-dichlorophenol aqueous solution with initial pH=7, the degradation rate could reach 91.5%. Moreover, the relationship between 2,4-dichlorophenol degradation rate and its initial concentration follows the Langmuir-Hinshelwood model. The variations of total organic carbon and Cl- were also inspected during the photocatalytic reaction. It is suggested that it is beneficial for the mineralization and dechlorination for 2,4-dichlorophenol by using nitrogen-doped bismuth oxide as photocatalyst.

Key words: nitrogen-doped bismuth oxide, photocatalysis, visible-light, dichlorophenol, kinetics