Study On Treatment Of Wastewater Containing Phenols With Doped PbO₂/Ti Electrode

At present, the quickly developing industry brings more and more pollution to the water. It has been the difficulty of the wastewater treatment for the disposal of biorefractory organics which can't be treated effectively by current ordinary waste water treatment technology.Doped Ti based lead dioxide electrocatalytic electrodes were prepared and their disposal effect and factors were estimated by treating organic wastewater,in order to do some fundamental work which may help the electrocatalytic oxidation technology to be actually applied in wastewater intreatment.Firstly, different ratios of Fe, Bi and Ni, Bi doped lead dioxide electrodes were prepared by electrodeposition, and were used to treat wastewater which contained phenol. The result showed that the electrocatalytic capability of doped electrodes had been improved, and the best one was Fe, Bi doped electrode with the ratio 1:1. This electrode could remove 75% of phenol in wastewater with a concentration of 80mg/L after 60 min under a current density of 10mA/cm².Secondly, the Fe, Bi doped electrode was used as anode, and the cuprum plate as cathode to degrade stimulant phenol wastewater. The factors such as current density, the space between anode and cathode, initial phenol concentration, pH, electrolyte concentration and time, were systematically researched in the process of degrading phenol. And the kinetics of phenol electrocatalytic oxidation was also discussed. The research showed the suitable conditions were 30mA/cm², pH=3, the space between anode and cathode was 1cm, and the electrolyte concentration was 0.1mol/L. The kinetics study of phenol electrocatalytic oxidation indicated that the electrocatalytic oxidation accorded with the apparent first-order kinetics law. Between the factors which had been discussed, the current density had the more distint influence upon the speed constant of kinetics. Another kind of Ti based lead dioxide electrodes was prepared by composite electrodeposition which was doped by CeO₂. The micrographs, element analyse of the surface of the doped electrode were analyzed with the help of SEM and EDS. The electro-catalytic performance of the electrode was reviewed by degrading stimulant phenol wastewater. Results showed that crystalline grain of the doped electrode distributed uniformly, and during the degrading process, the pressure was about 0.1 V lower than using traditional electrode.