Preparation And Catalyst Performance Research Of SnO₂ Particle Electrode

At present, it has been the crux of the waste treatment due to lack of effective ordinary treatment technology for the waste water containing toxic and non-degradable organics. All the organics in the waste water are usually great harmful to the environment and human. The electrochemical oxiadation processes have attracted a great deal of attention because of their versatility, environmental compatibility, and especially, destruction of toxic and non-biodegradable organics by direct or in direct anodic oxidation. But there was low area-volume ratio and low current efficiency in traditional two-dimensional electrode. In three-dimensional electrode, big area-volume ratio and small space among particle electrodes, gave it higher current efficiency, which made it become the breakthrough in the electrochemistry technique. The performance of particle electrode have very important effect on three-dimensional electrode method in water treatment technology.Various catalysts with different active metals, i.e. Mn,Fe,Cu,Zn,Co,Ni and Sn were loaded respectively on the surface of Al2O3 particles as the particle electrode by impregnating and roasting method. Electrocatalytic oxidation of phenol was investigated in the presence of one of these particle electrodes. It is shown that Al2O3-SnOx particle electrode could greatly improve the degradation of phenol and TOC and indicate SnOx is the best catalysts in the electrochemistry technique.Surface metallization on alumina ceramic was realized by electroless copper plating. Then Tin was covered in the copper by electroless tin plating. the particles were annealed in an oxidizing atmosphere at 550℃for 6h to obtain the SnO2 particle electrode. Microstructure of the metallized copper layer was studied by SEM, XRD and Cyclic voltammetry, The experiment indicates that the surface of the particle electrode was compact, no crack and SnO2 was composition of it. Experiment for treatment of waste water containing phenol shown that the Current efficiency of the three-dimensional electrodes is 32.42 mgTOC/Ah and improved a lot than 14.07 mgTOC/Ah of the two-dimensional electrodes.The effects on phenol degradation were investigated, In the experimental of phenol degradation, The result shown that acidic and alkaline conditions could all accelerate the degradation of phenol, but make against the degradation of TOC. Concentration of phenol and TOC removal rate is increased as the increase of current density, but current efficiency decreased. The optionl air flow is 0.15 m3/h, and the optionl concentration of Na2SO4 is 0.05mol/L.