The Experimental Study On The Treatment Of Dye Wastewater By The Photoelectric Fenton Oxidation

In recent years,with the rapid development of dyestuff industry,all kinds of biological refractory organic dye wastewater increased accordingly,electrochemical technology with its unique advantages shows a good application prospect in the field of wastewater treatment,especially photoelectric Fenton oxidation advantage is obvious.Photoelectric Fenton oxidation coupling the advantages of the technique of electrochemical oxidation and Fenton,the pollutants can be almost degradation of no choice in wastewater,therefore it has been attracted much attention.The study comprehensively expounds photoelectric Fenton oxidation mechanism of acid scarlet dye wastewater treatment and its operating conditions,and analyzing the degradation of acid scarlet regularity in for treatment of refractory organic wastewater the method provides reference for the further study of the direction.This study test apparatus for homemade electrochemical reactor,treatment object for homemade simulated acid scarlet dye wastewater,the main of research content includes:the choice of electrode materials;Two methods of electrochemical oxidation degradation of acid scarlet of the comparison of the effects and energy consumption;Test of different operating conditions on the photoelectric Fenton oxidation effect of acid scarlet processing and response surface analysis;Photoelectric Fenton oxidation of acid scarlet dye wastewater degradation kinetics and UV-visible spectrum analysis.The acid scarlet decolorization rate and COD removal rate as the evaluation index in the photoelectric Fenton oxidation system and electric Fenton oxidation system,using iridium coating of oxygen electrode as anode,and using Ti electrodes,stainless steel electrode and graphite as cathode,was selected to simulate acid scarlet dye wastewater degradation effect the best electrode,the results show that Ti electrodes is the best within the scope of this test to investigate the cathode electrode.Electric Fenton oxidation and photoelectric Fenton oxidation to contrast experiment shows that the acid scarlet dye wastewater treatment on the dye degradation effect,the photoelectric Fenton oxidation than electrical Fenton oxidation decoloration rate is higher 35.72%,removal rate of' COD is higher 12.94%;Photoelectric Fenton oxidation system than electrical Fenton oxidation system energy-saving,the decolorization rate was 90%,Photoelectric Fenton oxidation power consumption is only 43%of the energy consumption of the electric Fenton oxidation.Through the single factors experiment.the initial dye concentration can not too high,if it too high will beyond the processing limit of reactor and against reaction;Voltage in a certain range,with the increase of cell voltage,dye wastewater decolorizing rate increased gradually;with the increase of air,reducing the Fe2+ content when has too much oxygen in the system,inhibition of Fenton reaction,acid scarlet wastewater decolorizing rate gradually decreased;When excessive amounts of Fe2+ dosing will consumes part of ·OH causing a significant drop in decoloring rate;there is an optimal value of pH on decolorization rate of system,when the pH is equal to 4,acid scarlet decolorization rate is the highest of 99.48%;Supporting electrolyte additive amount on decoloring rate of system has optimal values,supporting electrolyte concentration of 2000 mg/L,the decolorization rate of wastewater,the largest up to 99.48%;Decoloring rate and the removal rate of COD present a tendency of increasing with the increase of reaction time,but in different period,increasing the size of the different.According to the Design Expert of Box-Behnken Design optimization analysis,the response surface model equation as follows:the decolorization rate = 52.66715-6.51838 × air+1.56952 × air × pH-0.045425 ×(Cell voltage)2-2.19265 ×(pH)2;Optimal operating conditions for:bath voltage is 15.73 V,air is 0.25 L/min,pH is 4.25,under the best operating condition,the decolorizing rate is 97.1869%.Through 3D response surface analysis,effect of various factors on the system of decolorizing effect size for:pH>cell voltage>air;Various factors interaction effects on decolorization of system size:slot voltage&pH>pH&air>cell voltage&air.Acid scarlet in photoelectric Fenton oxidation degradation conform to the first order kinetic model,the dynamic equation is-lnCt/Co= 0.0454t;By ultraviolet-visible absorption spectrum analysis shows that acid scarlet wastewater decrease of concentration during the treatment in photoelectric Fenton oxidation process,and the effect is well.The molecular structure of the acid scarlet color system is gradually degrade damage along with the increase of reaction time,the dye molecules in the basement and aromatic structure destroyed by degradation,finally is broken down into small molecular compounds,and it mineralized into carbon dioxide and water.Photoelectric Fenton oxidation processing acidic scarlet decolorization effect is remarkable,the operation is simple,but this article uses the two-dimensional plate electrode,the electrode of the effective area is small,compared with electric Fenton oxidation process more efficient,suggest further studies,perfect after can be used in engineering practice.