Study On The Treatment Of Reactive Brilliant Orange X-GN By Bipolar Electro-Heterogeneous Catalytic Oxidation Method

In recent years, electrochemical technology with its peculiar advantages come show good application prospect in the field of wastewater treatment, especially the emergence of three dimensional particle electrode pioneered the electrochemical treatment of wastewater in the new period. At the same time, heterogeneous catalytic oxidation treatment as a new technology, which is the use of a solid oxidant to accelerate oxidant decomposition before generating oxidative more groups, was aroused widespread concern as no secondary pollution, recyclable solid catalyst advantages. In this paper, the electrochemical and heterogeneous catalytic oxidation technology was combined organically, with bipolar packed bed cell as reactor, the traditional insulation fillers was replaced by the load transition metal oxide heterogeneous catalyst in the reactor, building electrical polarity-heterogeneous catalytic oxidation system. With Azo dye Reactive Brilliant Orange X-GN as electrolytic substrate, this method was studied systematically through mechanism of action and process conditions to removing Reactive Brilliant Orange X-GN.In this study, experimental apparatus was the homemade electrochemical reactor; treatment object was simulated dye wastewater-Reactive Brilliant Orange X-GN, main research contents include:the development of heterogeneous catalysts; the research to single factors the corresponding surface through treatment of reactive brilliant orange X-GN by bipolar electro-heterogeneous catalysis reactor. Comparative study that treatment of reactive brilliant orange X-GN by bipolar electro-heterogeneous catalytic oxidation method and the bipolar three-dimensional electrode method. Reactive Brilliant Orange X-GN degradation kinetics and UV-visible spectroscopy was analysised.The decolorization rate of reactive brilliant orange X-GN as evaluation standard, prepared by the impregnation method,5 kinds of catalyst carrier respectively, ?-Al2O3,13X,3A,4A,5A and 4 kind of active ingredient respectively CuO?Fe2O3?NiO?ZnO were screened, the CuO/?-Al2O3 is within the scope of the study the optimal performance of catalyst. And further optimize the preparation conditions of CuO/?-Al2O3 concluded:in the condition of Immersion time was 20h, dipping temperature was 25?, soaking liquid Cu content of 7%, calcination temperature was 500?, Ce additives mixed mass fraction of 3%, The prepared catalyst has high activity, good stability, in the SEM characterization of crystal clear, firm structure, specific surface area and surface roughness are large, with porous catalyst requirements.Through the single factor experiment conclude voltage exists an optimum value for the decolorization of dye, exceeds the optimal value, energy consumption increased significantly; the value of pH for the acidic conditions conducive to the reaction, bipolar electro-heterogeneous catalytic oxidation system on the pH value of strong adaptability; inlet dye concentration should not be too high, too high concentration will pollute catalyst, and beyond the limit of management of reator, in response to adverse; electrolyte adding concentration in certain voltage conditions, the dosage is bigger, better treatment effect; proper aeration can enhance mass transfer rate, strengthen the stirring effect; particle electrode dosage has an optimal value, excessive dosage is not obvious to removal rate of dye. According to Box-Behnken Design response surface analysis, the following main conclusions.model equation was:decolorization rate=80.83570+3.49894×cell voltage -5.77×pH value +0.12412×cell voltage×pH value-0.1176×(cell voltage)) 2+0.19469×(pH value) 2; Influence degree of various factors on decolorization rate was cell voltage> pH values> dosing electrolyte concentration. Influence degree of the interaction between various factors on the decolorization rate was the cell voltage-pH values> cell voltage-electrolyte dosing concentration> pH value-adding electrolyte concentration. The optimal operating conditions for the cell voltage was 17.84V, the pH value was 7, concentration of electrolyte for investment 966mg/L, the decolorization rate of up to 95.5% in this condition.Comparison of experimental results of bipolar electro-heterogeneous catalytic oxidation method and the bipolar three-dimensional electrode method to treatment of reactive brilliant orange X-GN shows effect of the removal of the former than the latter 10% or more, in terms of energy consumption, the decolorization rate was higher, the advantages of bipolar electro-heterogeneous catalytic oxidation method was more obviously, when the decolorization rate of 90%, comparing with the bipolar three-dimensional electrode method, bipolar electro-heterogeneous catalytic oxidation method saved nearly 50 percent energy.The process of decolorization on Reactive Brilliant Orange X-GN by bipolar electro-heterogeneous catalytic oxidation method met a kinetic model. By the UV-visible absorption spectroscopy shows that reactive brilliant orange X-GN concentration was decreasing during oxidative degradation, the effect of degradation was better, its molecular azo conjugated hair color system and the naphthalene ring structure was destroyed, and azo conjugated color system was more easily destroyed and eventually were mineralized to CO2 and H2O2.This research has shown that bipolar electric-heterogeneous catalytic oxidation method for reactive brilliant orange X-GN removal effect was remarkable, the operation was simple, and cover area was small. The method was better efficiency than traditional bipolar three-dimensional electrode method, through further research and improvement, can be used in engineering practice.