Research Of Ti/PbO₂ Electrodes Degradate Organic Pollutants

This article examined the layer on the lead dioxide of titanium firstly.Three different types of Ti-base lead dioxide eletrodes including Ti/β-PbO₂,Ti/SnO₂+Sb₂O₃/β-PbO₂ and Ti/α-PbO₂/β-PbO₂ were successfully prepared using thermal decomposition and electrodeposition.Their performance was characterized through SEM, XRD and anodic polarization curves.The electrochemical oxidation in the target pollutant of 2-chlorophenol and the electrode life of this three eletrodes were aslo studied.The results show that the mid-layer has a significant impact on the morphology and catalytic activity of active layer. Ti/α-PbO₂/β-PbO₂ eletrode in the three electrodes has the maximum oxygen evolution potential in 2-chlorophenol aqueous solution with the removal rate of 99.3%,a longer electrode life and a lower cell voltage.In addition,2-chlorophenol degradation by the three kinds of electrodes follows the first kinetics.Then prepared two series of catalytic electrodes using Titanium plate and titanium mesh respectively. The electro-catalytic degradation of 2-chlorophenol using electrodes with different substrates, different the middle layers and activity of the outer layers were investigated.The results indicated that combination property of the electrodes on the Ti plate are better than the electrodes on the Ti mesh and Ti-base lead dioxide electrodes withβ-PbO₂ active layer are better than electrodes with RuO₂.In addition,the degradation of 2-chlorophenol all followed the first kinetics on six electrodes. The optimum eletrode was Ti/α-PbO₂/β-PbO₂.The optimum condition of degradating 2-chlorophenol was investigated by orthogonal test. The results showed that the optimum process condition for electro-catalytic degradation of 2-chlorophenol using the electrode: initial concentration of 2-chlorophenol was 50mg/L, electrolyte concentration of Na₂SO₄ was 0.2mol/L, temperature was 35℃and anode current density was 20mA/cm². Degradation of the 2,4-dichlorophenol and bisphenol A were investigated in the optimum conditions and mechanism of degradating 2-chlorophenol was studied. The results showed that Ti/α-PbO₂/β-PbO₂ electrodes have high electrocatalytic activity for different organic pollutants.