Research On Ti/SnO₂-RuO₂ Electrode For Electrocatalytic Degradation Of Four Typical Dyes Wastewater

With the development of modern industry,dyes are widely used in various industries.However,a large amount of wastewater is generated during the production and in the practical application of dyes.Dye wastewater has the characteristics of high chroma,Chemical oxygen demand?COD?and toxicity,which is harmful to human health and ecological environment.Therefore,effective treatment of dye wastewater has become a hot spot.Electrocatalytic oxidation is widely concerned due to high electrocatalytic degradation efficiency,simple technical equipment and low energy consumption,etc.The efficiency of electrocatalytic degradation is highly dependent on the characteristics of the electrode materials,so it is very important to choose the suitable anode materials.In this thesis,Ti/SnO₂-RuO₂ electrode and Ti/RuO₂ electrode are prepared by thermal decomposition method.The physical characteristics of electrodes are characterized by scanning electron microscope,X-ray diffractometer and X-ray fluorescence spectrometry,respectively.The electrochemical performances of electrodes are studied.Ti/SnO₂-RuO₂ electrode is investigated to degrade four typical dyes wastewater?alizarin yellow,crystal violet,alizarin cyanin green and methylene blue?.The main contents are as follows:?1?Alizarin yellow is used as simulative dye wastewater,and we investigate the effects of p H,current density,electrolyte concentration and temperature on the electrocatalytic degradation of alizarin yellow dye wastewater on as-prepared electrode in sodium sulfate electrolyte.The results indicate that the degradation efficiency and removal rate of COD of alizarin yellow are 82.8%and 54.3%,respectively,under the condition of current density 8.0 mA·cm^-2,electrolyte concentration 10.0 g·L^-1,pH 7and electrolytic temperature 35°C.Kinetic analysis shows that the degradation process accords with the first order kinetics law.?2?The effect of as-prepared anodic electrode on the electrocatalytic degradation of crystal violet dye wastewater is investigated in sodium chloride electrolyte.The results of orthogonal experimental show that the order of influencing factors from high to low are as follows:current density,electrolyte concentration,p H and temperature.The results of the single factor experiment indicate that the degradation efficiency and removal rate of COD of alizarin yellow are 98.9%and 85.3%,respectively,with the condition of current density 2.5 mA·cm^-2,electrolyte concentration about 2.5 g·L^-1,pH 7 and electrolytic temperature 25°C.?3?The effects of p H,current density,electrolyte concentration and temperature on the electrocatalytic degradation of alizarin cyanin green dye wastewater are investigated by as-prepared anodic electrode.The results indicate that the degradation efficiency and removal rate of COD of alizarin cyanin green are 80.4%and 51.2%,respectively,under the condition of current density 3.0 mA·cm^-2,electrolytic temperature 25°C,pH 5 and electrode distance 1.0 cm.Kinetic analysis shows that the degradation process accords with the pseudo first order kinetics law.?4?Methylene blue is used as simulative dye wastewater,and we further discuss the effects of p H,current density,supporting electrolyte and temperature on electrocatalytic degradation of methylene blue dye wastewater on as-prepared anodic electrode in sodium chloride electrolyte.The results demonstrate that degradation efficiency and removal rate of COD of methylene blue dye wastewater are 92.6%and 86.6%,respectively,under the condition of pH 7,current density 4.0 mA·cm^-2,electrolyte concentration 3.0 g·L^-1 and electrolytic temperature 25°C.Kinetic analysis shows that the degradation process accords with the first order kinetics law.The results demonstrate that Ti/SnO₂-RuO₂ electrode possesses excellent electrocatalytic property for four typical dyes wastewater and further show great potential application in dye wastewater treatment.