| The phenolic compound is an organic compound, which can hardly be degraded. It is a toxic material with latent possibility to cause cancer, abnormality, and aberrance as well. It is also an aquatic and main pollutant that exists in industrial wastewater coming from the oil refining, coke, deckle, plastics, chemical engineering etc. Various traditional methods of disposing of wastewater containing phenolic compound such as physics, chemistry, biological chemistry, do not function properly because of them shortcoming. Along with the development of the environmental protection technique and the improvement of demand for the quality of water, heterogeneous photocatalytic degradation technique gradually developing in the last twenty years can effectively degrade the phenolic compound that is not easy to dispose. Photocatalyticdegradation of the phenoic compound wastewater is a treatment that mineralize the phenoic compound into CO2, H2O or non-toxic organic compound thus achieves the demand for non-toxic process . Comparing with other disposition of wastewater, this method has the property such as energy conservation, much more complete degradation, simple technics, which shows a great perspective in the field of disposition of wastewater.The author develops a new type of photocatalyst, which has a wider responding value to the sunlight than the classic one--TiO2, and possesses good performance of photocatalytic degradation. This photocatalyst has nice applied perspective. This paper synthesizes a series of photocatalyst with various methods. Analyses and assessment of catalyst activity is carried out. It is found that both Bi2O3-V2O5 and Bi2O3-Y2O3 have higher activity than others. Various influencing factors in the process of preparing catalyst have been taken into consideration, for an instance, the ratio of materiel, baking temperature, baking time. The modern technology is used in the characterization of photocatalyst, for example, DRS, XRD, TG-TDA, DSC, FT- IR, and PLS as well. All the data gained in the experiment are related with the data from the assessment of catalyst act ivity, and finally the relationship of catalyst capacity with itsstructure is given out.The research shows, the Bi2O3-V2O5 catalyst has the best activity with the material(Bi2O3 and V2O5) ratio by 1:1, baking temperature by 850 C, baking time by 9h, the ratio of degradating 2,4-dichIorophenol reach by 86.6%, increase by 11.0% comparing to pure Bi2O3.The analysis found that the band gap of Bi2O3-V2O5 catalyst is 2.4 eV, and narrower than TiO2(3.2eV). The research shows ,the Bi2O3-Y2O3 catalyst has the best activity with the material (Bi2O3 and Y2O3) ratio by 1:0.5, baking temperature by 850 "C, baking time by 9h,the ratio of degradating 2,4-dichlorophenol reach by 92.7%, increase by 17.1% comparing to pure Bi2O3. The analysis found that the band gap of Bi2O3-Y2O3 catalyst is 2.2 eV. The surface of Bi2O3-V2O5 catalyst has hydroxyl and oxygen defects in abundances, which is supported by the PLS and FT-IR experiment. Catalyst under irradiation of mercury lamp can produce many electron-positive hole to favor the photocatalytic degradation reaction, since it has narrow band gap. It indicates in term of condition of technology that when photocatalytic reaction goes in the solution with 2,4-dichlorophenol wastewater concentration about 50mg/L, the best dose of catalyst is 0.375 g/L, pH 6.0 H2O2 50mL/L, the degradation rate accords with Langmuir-Hinshelwood kinetics at low concentration but irrelevant to original con-centration at high in 2,4-dichlorophenol degradation reaction.
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