| Landfill leachate is a high concentration organic waste water, it has specialities of intricate components, high concentration of contaminations, large variety of water components and quantity. There has no integrity process for landfill leachate treatment at present.Ferrate is the iron present iq+n the hexavalent form, it has the molecular formula of FeO42-.Ferrate could be employed in the water treatment because of its specialties in disinfection, oxidization, flocculation, adsorption and coagulation-promotion. The Fe3+ photocatalytic oxidation method has the specialties of low energy consumption, suavity reaction conditions, etc. The reaction could be carried through normal temperature and normal air pressure, and it can oxidate the organic infectants into CO2,H2O and acid completely at short time. Whereas the ferrate's strong oxidation, the production's adsorption and flocculation, and the (Fe3+)'s photo-catalyzatic ability, the article design the photochemical oxidation combined with ferrate pre-treatment method for landfill leachate treatment.This study produced ferrate through DC-electrolysis , and determined the concentration of ferrate formed in anode electrolyte using UV-visible spectrophotometer. The study indicated that when electrolyte pressure was 6V, temperature was 30℃, 2.5 hours later, the concentration of ferrate could reach 22.8mmol/L. The experiment used newly-produced ferrate ever time, which solved the disadvantage of ferrate for example easily decomposing, not suitable for storage. The study indicated that in room temperature, when dosage of ferrate was 25.6mg·L-1(counted by iron), pH=4,30min later, the leachate could achieve 46% of COD removal, 20% of NH3-N removal, 83% of total-P removal and 89% of color removal.The study compared the four photo-reaction system: UV, TiO2/UV, (Fe(Ⅵ)/UV), Fe(Ⅵ)/TiO2/UV for leachate treatment,and it indicated that the leachate was under photo-catalyzation after the ferrate pre-oxidation treatment, COD,NH3-N,total-P could achieved a much deeper removal. Fe(Ⅵ)/TiO2/UV system is the most efficient process for leachate removal, when illumination for 4 hours, COD,NH3-N,total-P could achieve 55.3%,60.3% and 100% removal respectively. Fe(Ⅵ)/ UV system could also achieve a good effect, when illumination for 4 hours, COD,NH3-N,total-P could achieve 50.4%,52.2% and 100% removal respectively.This study invented the combination of ferrate pre-oxidation and TiO2 photo-catalyzation for landfill leachate treatment for the first time, it studied the optimal pH, dosage of ferrate, reaction time, temperature when ferrate was used for leachate treatment, and it also studied the photo-catalyzation method for the deeply treatment of landfill leachate, which provides an important academic instruction on the treatment of high concentration organic wastewater.
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