Study On Preparation Of Titanium-Substrated Lead Dioxide Electrode And Application To Organic Wastewater Treatment

With the problem of water pollution becoming more and more serious, people are interested in the methods of various sewage treatment especially refractory organic wastewater.The electro-catalytic oxidation process attract the eyes of many environmentalists due to its inherent advantages.Electrodeposition approach was employed to prepare Ti/PbO₂ electrodes, and sol-gel method was applied for electrode modification, fabricating unique constructed electrodes,which was Ti/SnO₂-Sb2O5/PbO₂ electrode,Ti/TiOx?NTs?-SnO₂/PbO₂ electrode. The effects of experimental conditions containing deposition time and intermediate coating number were investigated respectively with some characterizing methods such as XRD, SEM,electrochemical measurements, decomposition test, accelerated life test and so on.Experimental results showed that the optimal conditions are the deposition time of 90 min,and the intermediate Sb-doped SnO₂ coating number of 10. It is determined that PbO₂ electrode with a 90 min deposition time possesses a accelerated service life of 2.10h, and a complete removal of 100mL 100mg/L phenol solution after 3 h processing. It is also revealed that PbO₂ electrode with the intermediate Sb-doped SnO₂ coating number of 9 has a a accelerated service life of 54.08h, whereas the electrode with the intermediate coating number of 10 has a a accelerated service life of 58.13h.Three kinds of PbO₂ electrodes were used to electro-catalytically degrading phenol,indigo carmine and methyl orange, investigating organic matter removal efficiency and COD removal efficiency. Experimental results show that the removal efficiency of indigo carmine and COD on the Ti/PbO₂ electrode are 100% and 47.04% respectively after 60 min processing,the removal efficiency of methyl orange and COD on the Ti/SnO₂-Sb2O5/PbO₂ electrode are 92.55% and 54.78% respectively after 120 min processing, and the removal efficiency of phenol and COD on the Ti/TiOx?NTs?-SnO₂/PbO₂ electrode are 100% and 51.03%respectively after 180 min processing.Through optimizing process parameters, the oxidation degradation of optimizing conditions of electrocatalysis reaction aimed at 200mL 1000mg/L indigo carmine when Ti/PbO₂ electrode is regraded as anode are:0.05 mol/L Na2SO4, space between polar plates is 3cm, 0.03 mol/L Cl-,pH=0.91,and 9min later the removal efficiency of indigo carmine reaches 95.0%;the oxidation degradation of optimizing conditions of electrocatalysis reaction aimed at 200mL 100mg/L methyl orange when Ti/SnO₂-Sb2O5/PbO₂ electrode is regraded as anode are:0.05 mol/L Na2SO4,space between polar plates is 3cm,0.04 mol/L Cl-, pH=1.02,and 5min later the removal efficiency of methyl orange reaches 90.6%.the oxidation degradation of optimizing conditions of electrocatalysis reaction aimed at 200mL 100mg/L phenol when Ti/TiOx?NTs?-SnO₂/PbO₂ electrode is regraded as anode are:0.1 mol/L Na2SO4, space between polar plates is 3cm,0.02 mol/L Cl-,pH=3.02, and 60min later the removal efficiency of phenol reaches 80.0%. And then, Experimental results show that the activated carbon what exist in the solution is benefit for the electrocatalytic degradation of organic matter.