[Degradation of organic contaminant in landfill leachate by photo-Fenton process].

In the present work, the treatment of landfill leachate was studied by photo-Fenton process. All photocatalytic experiments were carried out under similar conditions on July or August sunny days between 12 a. m. and 14 p. m. in Chongqing based on the change in solar light intensity with time. The effect of operating conditions such as Fe/H2O2, pH value and Fenton's reagent dosage on color removal and UV254 was investigated. The UV-Vis absorption spectra of 1.00 X 10(3) mg x L(-1) landfill leachate were considered before and after photo-Fenton experiment. The experiment result indicated that photo-Fenton process can effectively remove color. The oxidation of organic materials in the leachate was pH dependent and the optimal pH was 2.5. The favorable Fe2+ to H2O2 molar ratio was 1/95. The optimal conditions in this research were Fe2+ concentration of 5.00 mmol x L(-1) and H2O2 concentration of 5.70 x 10(2) mmol x L(-1). Meanwhile, the analysis of reaction kinesics was carried out in the research. Second-order kinetic was observed for the degradation of landfill leachate, and the rate equation of photo-Fenton process was -dc/dt = -4.34[c]1.92. The result of UV-Vis spectra of landfill leachate showed that photo-Fenton process is an effective method for removal of organic compounds.