Visible light irradiation combined with homogeneous iron and/or hydrogen peroxide to degrade organic dye rhodamine B (RhB) and small molecular compound 2,4-dichlorophenol (2,4-DCP) in a home-made bottle reactor was assessed. The concen-tration of oxidize species, Fe3+ and Fe2+ were determined during the degradation process. The results demonstrated that visible light irradiation combined with electro-Fenton improved the degradation efficiency. Moreover, both RhB and 2,4-DCP were mineralized during visible light synergistic electro-Fenton oxidation process. 95.0% TOC (total organic carbon) removal rate of RhB occurred after 90 min and 96.7% of COD (chemical oxygen demand) removal rate after 65 min of irradiation. 91.3% TOC removal rate of 2,4-DCP occurred after 16 h of irradiation and 99.9% COD removal rate occurred after 12 h of illumination. The degradation and oxidation process was dominated by the hydroxyl radical ( · OH) generated in the system. Both the impressed electricity and dye sensitization by visible light facilitated the conversion between Fe3+ and Fe 2+ , thus, improving Fenton reaction efficiency.
展开▼