The Photocatalytic Degradation Of Dyes With The Supported Titanium Dioxide

China has posessed the largest textile dyeing industry in the world, and the statistical data show that the wastewater effluents from textile industry account35percent of the total discharge of industrial wastewaters in China. Therefore, the development of effective technology for wastewater treatment has become very important for protecting water environment and promoting continuable development of economic, society and environment.In this thesis, the different supports are adopted to load TiO2as photodegradation catalysts and their degradation of dyes is studied. The primary contents are as follows:(1) Nano TiO2activated carbon (AC) photocatalyst was prepared by sol-gel method and its photocatalytic activity and degradation mechanism toward Methylene Blue (MB) was investigated. The results showed that photodegradation efficiency of TiO2is increased by adding AC. When TiO2was0.5g/L and AC was0.2g/L, the degradation efficiency of TiO2was the highest. Besides, the value of initial concentration of MB has an important impact on photocatalytic activity. The adsorption and photodegradation capacity decreases with the increase of initial concentration. Meanwhile, the effects of three anions of Cl-, SO42-and NO3-on the photocatalytic activity were also investigated, and the effect sequence is NO3-> SO42-> Cl-.(2) Nano tungsten trioxide (WO3)-TiO2/AC composite photocatalyst was also prepared by sol-gel method. The Factors such as doping amount of tungsten, calcination temperature, pH and hydrochloric acid treatment, which influence catalytic activity, were also investigated. Compared to TiO2/AC and TiO2catalysts, the WO3-TiO2/AC catalyst exhibits higher catalytic activity toward Rhodamine B(RhB).(3) TiO2/graphene (GE) composite photocatalyst was synthesized using the sol-gel method. The photocatalytic degradation activities of TiO2, TiO2/GE-1and TiO2/GE-2were evaluated on degradation of MB and RhB. The photocatalytic degradation activity sequences of the different catalysts are TiO2/GE-2> TiO2/GE-1> TiO2. (4) Using carbon fiber (CF) as the support, TiO2/CF and GE/TiO2/CF composite catalysts were prepared. The photocatalytic degradation activities of the catalysts toward MB and RhB were studied. The results of the photocatalytic degradation activities for MB and RhB showed that GE/TiO2/CF exhibits higher photocatalytic activity than TiO2/CF.