Removal of Chelated Copper by TiO2 Photocatalysis: Synergetic Mechanism Between Cu (II) and Organic Ligands

Document Type: Research Article


1 Faculty of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China

2 Lin, Longli *+; Liu, Guoguang; Lv, Wenying; Qintie Lin, Kun Yao Faculty of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China

3 Faculty of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China

4 College of Chemistry and Chemical Engineering, Bijie University, Guizhou 551700, China


UV/TiO2 photocatalysis of chelated copper in aqueous solutions has been performed starting from Cu(II)-tartaric acid, Cu(II)-citric acid, Cu(II)-EDTA and Cu(II)-DTPA,in the presence of oxygen and at acidic pH. The photocatalytic reaction obeys first-order kinetic equation. The influence of Cu(II) on photocatalytic oxidation of organic ligands and how the various organics will affect the treatment of Cu(II) were described. A significant synergistic effect was observed between the reduction of Cu(II) and oxidation of organic ligands. The results prove that TiO2 photocatalysis is an effective approach for removing chelated copper from wastewater. 


Main Subjects

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