| Pentachlorophenol (PCP) is a typical kind of chlorinated organic pesticide and is also a kind of persistent organic pollutants (POPs), which can cause cancer, monstrosity and mutation. As one of the seven biggest rivers in China, Haihe River has been severely polluted recently. Studies show that level of PCP is higher than other organic pollutants. As a result, control on the pollution of PCP is paramount for the contaminent control in Haihe River.In this thesis, a method for the determination of PCP is established after comparing liquid-liquid extration (LLE) and ultrasound extraction (UE).Heterogeneous photocatalytic oxidation on TiO2 is adopted as the method of degradation of PCP. Frist, the adsorption of PCP on TiO2 follows Langmuir equation through the adsorption experiment. The study on kinetics shows that PCP can be effectively removed by photocatalysis and the reaction of degradation of PCP follows first-order kinetics model. GC-MS analysis shows that three intermediates, 2,3,4,5-tetrachlorophenol, 2,3,4,6-tetrachlorophenol and 2,5-dichlorophenol have been found in the process of degradation of PCP in aquatic solutions with photocatalysis.However, there are some demerits of photocatalysis, such as the low photo- catalytic quantum efficiency, which hamper successful application of photocatalysis on commercial scale for wastewater treatment. In order to overcome the defects, photocatalysis assisted ultrasonic technology(PAU) is choosen and the study on kinetics show that the combination of ultrasonic and photocatalysis significantly enhances the degradation efficiency. Through the reaction of MB shows that PAU can produce more hydroxyl radical ( OH) than photocatalysis.Photocatalytic degradation of PCP in aquatic solutions was designed by the orthogonal experiment. In order to optimize the conditions of reaction, the chart of tendency about factors and aim function that is obtained through analysis of the orthogonal experiment is drawen.
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