Abstract: The degradation of five naphthalene derivatives in the simulated wastewater was investigated using the iron-carbon micro-electrolysis method. The optimal initial pH of solution and adsorption of iron-carbon and removal efficiency of the total organic carbon(TOC) were investigated. The results show that the removal efficiency of the naphthalene derivatives can reach 48.9%−92.6% and the removal efficiency of TOC is 42.8%−78.0% for the simulated wastewater with 200 mg/L naphthalene derivatives at optimal pH of 2.0−2.5 after 120 min treatment. The degradation of five naphthalene derivatives with the micro-electrolysis shows the apparent first-order kinetics and the order of removal efficiency of the naphthalene derivatives is sodium 2-naphthalenesulfonate, 2-naphthol, 2, 7-dihydroxynaphthalene, 1-naphthamine, 1-naphthol-8-sulfonic acid in turn. It is illustrated that the substituents of the naphthalene ring can affect the removal efficiency of naphthalene due to their electron-withdrawing or electron-donating ability.

Key words: cast iron scrap; micro-electrolysis; naphthalene; substituent; wastewater treatment