Study On Pipeline Micro-Spe Ozone Generator

This paper develops a pipeline micro-SPE ozone generator, which is a miniature ozone generator installed at the top of the pipe with flowing water as the electrolysis environment. It can be used in water disinfection and purification devices. The micro-SPE ozone generator chooses Nafion membrane and pure water as the electrolyte, high oxygen evolution overpotential electrode as anode, hydrogen electrode as cathode. In order to improve the performance of ozone generator, preparation and optimization of anode materials has been studied. The PbO₂/SPE composite membrane electrode is prepared by theβ-PbO₂ directly depositing on the Nafion membrane. The crystalline structure and morphology are analyzed by XRD and SEM. Results show that the deposited layer on the Nafion membrane is single tetragonalβ-PbO₂ with 300～500 nm of particle size. The electrochemical performance of the PbO₂/SPE composite membrane electrode is compared to other two PbO₂ electrodes. The results show thatβ-PbO₂/SPE membrane electrode is more suitable for anode material in Pipeline micro-SPE ozone generator. When the current density is 1.5A·cm-2,the micro-SPE ozone generator can obtain ozone output of 49.64mg·h^-1, current efficiency of 14.1%, cell voltage of 4.33V and power consumption of 102.7Wh·（gO3）-1. During PbO₂/SPE composite membrane electrode as anode in the micro-SPE ozone generator, Electrolyte temperature and cell voltage are hold at 30℃and 3.8V, the current efficiency and the ozone output eventually are 26mg·h^-1 and 11% , and the PH value is between 6.7 7 over a period of 400 hours’operation. In summary, directly precipitated PbO₂/SPE composite membrane electrode as the anode has a stable performance, suitable for practical application.In addition, SnO₂, Sb/SnO₂ and Ce/Sb/SnO₂ material have been prepared by the direct chemical precipitation method. Composite membrane electrodes are made by hot-pressing method. Electrochemical properties in 0.1mol·L-1 H2SO4 solution has been studied by anodic polarization. The results show that Ce/Sb/SnO₂ membrane electrode has better electrocatalytic performance than other two electrodes. The ozone properties of above three membrane electrode are investigated by Galvanostat experiments. Ce/Sb/SnO₂ membrane electrode can markedly improve the catalytic performance. Under i=1.25A·cm-2, the micro-SPE ozone generator can obtain ozone output of 31.04mg·h^-1, current efficiency of 10.58%, cell voltage of 5.68V and power consumption of 179.4Wh·（gO3）-1.