Research On Preparation Of Activated Carbon Supported Titanium Dioxide And Photoelectrocatalysis Performance

With the development of science and technology, the society is improved constantly, while itbrings many environment problems at the same time. Water pollution has always drawn people’sattention. Advanced Oxidation Technology, which is capable of removing organics completely and isnot producing secondary pollutant, has a promising prospect in pollutant degradation as a newwastewater treatment technology. Titanium dioxide photocatalysis technology, a part of AdvancedOxidation Technology, has been widely used in the field of water pollutant degradation and airpurification due to its excellent photocatalysis performance, high chemical stability, low cost andnon-toxicity. However, titanium dioxide has some limitations so that it tends to develope new titaniumdioxide catalyst with visible light response and high photo-specular quantum efficiency.In this article, nano titanium dioxide was prepared by sol-gel method and deposited on activatedcarbon. The structure and property of the catalysts were characterized by X-ray diffraction, scanningelectron microscopy, the nitrogen absorption and so on. The conclusion is as followed. The titaniumdioxide particles were well deposited on the surface of the activated carbon. The specific surface areaof activated carbon decreased a little due to the titanium dioxide particles deposited on the pores ofactivated carbon. Activated carbon, as a carrier, mainly improved the absorption in the visible lightarea for the composite catalysts.In this article, methylene blue was considered as the research object, the photoelectrocatalysisperformance was evaluated by the degradation of methylene blue. The conclusion is as followed. Thecatalyst, which was calcinated at600℃, has the highest photoelectrocatalysis performance. Itsremovel rate of methylene blue was94.7%after90min. The optimal parameters of methylene bluephotoelectrocatalysis degradation were obtained by orthogonal experiment. The time was90min, theconcentration of catalyst was0.2g·L^-1, the voltage was15V, the concentration of electrolyte was0.5g·L^-1, the initial concentration of methylene blue was25mg·L^-1. From the research of UV-visabosrption spectrogram in the process of methylene blue degradation, it was observed that theabsorption peeks, which were at664nm,619nm and293nm, decreased gradually and disappeared atlast. The emergence and increase of the photocurrent explained that the bias voltage couldsignificantly increase the photocatalysis activity. It was proved that hydroxyl radical existed andplayed an important role in the process of photocatalysis by high performance liquid chromatography,and the concentration of hydroxyl radical was linear to the peek area of the resultant.