Study On Treatment Of Electroplating Additive Production Wastewater By UV-Fenton Associated With TiO₂Photocatalysis

With the rapid development of China’s electroplating industry, the usage of plating additives is increasingly widespread while the pollution caused by its production of wastewater has aroused great attention and concern. Electroplating wastewater was of complex water quality, high toxicity and hard to bio-degradable. For the disadvantages of low processing efficiency, poor effluent quality and unstable treatment effects, the approach of wastewater treatment is unable to meet the increasingly stringent environmental standards. Fenton process is one of advanced oxidation technologies which has been universally applied. As a new water treatment technology developed in recent years, photocatalytic technology has series advantages, such as of high treatment efficiency, degradated completely, non-selective, both oxidation and reduction, no secondary pollution. Addition to that, synergistic effect would occur between the combination of Fenton process and photocatalytic technology.Based on the research at home and abroad, electroplating additive production wastewater was treated by UV-Fenton with the association of TiO2photocatalysis in this research. The best reaction conditions was reached through the analysis on COD degradation:the concentration of H2O280mL/L of FeSO4·7H2O6g/L, and TiO2concentration of1g/L, pH=4, the reaction time was60minutes. The COD removal rate can reach94.9%.The wastewater treatment effects of H2O2, UV-H2O2, UV-TiO2, UV-H2O2-TiO2, Fenton, UV-Fenton, UV-Fenton-TiO2were compared separately in the experiment which proved the promotion on the Fenton processing efficiency of UV, TiO2, oxalic acid; reaction time, pH, H2O2dosage of FeSO4·7H2O dosage concentration, Fe2+and H2O2molar ratio and other factors on the processing efficiency were investigated.It showed that there was a good synergistic effect with Fenton and TiO2photocatalytic method, the processing efficiency of the Fenton process has been improved; effluent COD reduced152mg/L, from7600mg/L of the original to388mg/L; H2O2dosage was reduced by20%, associated with TiO2photocatalysis.