Preparation Of High Performance Lead Dioxide Electrodes And Its Electro-oxidation Degradation Of Organic Wastewater

In recent years,the problem of water pollution is becoming more and more serious in China.Electrochemical oxidation technology has become a research hot topic in hard degradation organic wastewater treatment,and the lead oxide(PbO2)electrode as the key technology of advanced oxidation,explore a way to improve its performance has been a major goal of researchers.At present,there are two main reasons affecting the stability of titanium based PbO2 electrode,a coating surface stress,produce coating stress cracking during use,due to the surface of the electrode is not compact and defects,the electrolyte gradually infiltrated into the substrate surface forming a passivation layer lead to electrode failure off.In order to improve the stability of PbO2 electrode,this paper put forward by pulse electrodeposition and doped polyaniline technology,study on effect of preparation process on the electrode performance,in order to PbO2 coating electrode was prepared by improved performance.The effect of electrolysis temperature,current density,initial pH value,forced mass transfer and pulse current on the COD removal rate of coking wastewater was investigated by using the prepared electrode.The main work and conclusions are as follows:(1)According to the function parameters of the new double pulse power supply,dual pulse power supply parameter for preparation of titanium based PbO2 electrode,the electrochemical properties of the electrode preparation,study on catalytic performance,surface morphology,crystal structure,optimize the process parameters of pulse electro oxidation deposition of PbO2 positive,60% duty cycle negative duty ratio of 10%,20 Hz pulse frequency,pulse waveform of 5 positive pulse number 1 negative pulse number is the best preparation of electrode performance.The PbO2 shaped anode material prepared by double pulse current is more compact and well crystallized than the PbO2 electrode prepared by DC power supply,and the crystal shows the preferred orientation of(110)crystal plane.(2)The conductive polyaniline(PANI)is added to the electrolyte,composite codeposition and PbO2,preparation of PbO2-PANI composite electrode system,results show that the polyaniline doped PbO2 electrode surface makes the particle size decreases,electrochemical and electro catalytic performance and electrode are improved.On this basis,combined with the ionic liquid assisted electrodeposition of [Emim]BF4 and optimization of pulse electrodeposition process,preparation of high performance PbO2-PANI composite electrode,the influence of the PbO2-PANI composite electrode performance of ionic liquid assisted,double pulse current mode for the preparation of the.The simulated wastewater COD,anodic polarization curves,AC impedance,surface morphology,crystal structure,accelerated life and IR removal of electro catalytic electrode materials were tested,compared and analyzed the influence of different preparation methods on the properties of PbO2-PANI composite electrode.The results showed that the electrochemical properties and electrocatalytic activity of the electrode prepared by adding [Emim]BF4 and PANI into Pb(NO3)2 were increased,and the surface of the electrode was more compact than that of PANI only.Using the properties of pulsed PbO2-PANI electrode current preparation is further improved,and the double pulse current electrode preparation is better than that of single pulse,pulse current in DC current is more conducive to the co deposition,is conducive to increasing the amount of doping conductive polymer coating;double pulse ionic liquid assisted PbO2-PANI composite electrode plating stability,compared to ordinary PbO2 catalytic activity a substantial increase.The infrared spectrum showed that polyaniline existed in the electrodeposition layer.(3)Use the double pulse current to optimize the preparation of PbO2 electrode as the working electrode,the electrocatalytic oxidation of coking wastewater treatment,results showed that the electrocatalytic degradation of coking wastewater,the higher the temperature of electrolyte and current density is more beneficial to the degradation of organic pollutant removal,but the larger current density is obviously not conducive to improve current efficiency.The original factory produced by coking wastewater is neutral to alkaline conditions(pH=9.28)better COD removal effect;mass transfer force using a self-made device,the electrolyte in the electrolytic process flow to improve the removal rate of COD,on this basis,the use of pulse electrolysis can obtain higher removal rate of COD.