Research On Preparation Of The Electrode Of Zn-Se/Stainless Steel And Treatment Of Simulated DyeWastewater By Ultrasound-Electrochemical System

Based on the research of degradation of dye wastewater by the electrochemical system of ultrasound- binode of titanium and iron, the cathode materials were modified by the Zn-Se films electrodeposited on the piece of stainless steel, and simulated dye wastewater was treated by the electrochemical system of ultrasound- the cathode of Zn-Se films electrodeposited and the binode of titanium and iron .Firstly, the technological parameters of the Zn-Se films electrodeposited on the piece of stainless steel were investigated. The results showed that the optimum electrodeposition conditions were those:the current density 3.8 mA·cm-2, the initial molality ratio of ZnSO4/Na2SeO3 250:1, the initial pH 2.9, the quality of sodium citrate 14.71 g, the time 7 min, the temperature 55℃,and the ultrasonic power 160 W. In the meantime, the films were characterized by SEM and EDAX. The results showed that the surface morphology of the films were homogeneous and compact, and the mass ratio of Zn and Se atoms was 1:1.5 (stoichiometry ratio was 1:1.25).Secondly, the treatment of simulated dye wastewater was prepared by the electrochemical system of ultrasound- the cathode of Zn-Se films electrodeposited and the binode of titanium and iron .The influence factors which affected degradation rate of Rhodamine B simulated dye wastewater, such as the electric current density, the initial pH value of wastewater, the ultrasonic power, the ventilation volume and the different cathode materials of Zn-Se films on the piece of stainless steel of mass ratio of Zn and Se, were investigated. In addition, the optimum technology conditions were investigated and verified by orthogonal design.The results showed that the best conditions were those:the electric current density 24 mA·cm-2, the initial pH 6, the ultrasonic power 160 W, the ventilation volume 10 L·h-1 and the mass ratio of Zn and Se 1:1.5. Under these conditions, the decolorization and COD removal rate were up to 98.97% and 88.11% after 120 min degradation.Thirdly, the comparative experiment of the treatment effect of simulated dye wastewater was investigated by the different cathode materials in the experimental system.The results showed that under the other same conditions the decolorization and COD removal rate in the condition of the cathode of Zn-Se films electrodeposited were higher than ones in the condition of the cathode of stainless steel. Finally, the mechanism of treating simulated dye wastewater was proposed. The experimental results showed that degradating process was two steps and every one followed a first-order kinetic model.