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In recent years, the endocrine system and reproductive system of animal and human frequently occur abnormal,for the disruption of environmental estrogens.These has been listed as another global major environmental issue after the destruction of the ozone layer and greenhouse effect. Estrone (El), estradiol (E2), ethynylestradiol (EE2), estriol (E3) and the alkyl phenol are main material caused the sewage plant effluent with estrogenic activity, and the El, E2, E3 and EE2 be with larger relative estrogenic activity (EEF). Bisphenol A (BPA) is a typical environmental hormone and one of industrial chemicals fastest-growing demand in China. Many studies have shown that BPA were detected in water, air, soil, sediment and environmental biofacies. It is difficult to completely remove the environmental estrogens by the conventional wastewater treatment process. So some of environmental estrogens still left in water. Although the concentration of environmental estrogens is typically measured at ng·L-1 orμg·L-1 level, its comparatively high activity of estrogen poses a great harm. In the study, BPA, E1, E2 and E3 were selected as the target compounds. We detected and analyzed the concentration of this four kinds of estrogens in Nanning conventional wastewater treatment plant by HPLC.The results showed that the concentration of BPA, E1, E2 and E3 in influent were 2.86、10.32、4.62 and 1.78μg·L-1, respectively, after the normal wastewater treatment, its removal rate was 69.7%,74.3%,47.0% and 70.2%, respectively. So the content of BPA, E1, E2 and E3 in effluent were 0.87、2.65、2.45 and 0.53μg·L-1, respectively.We known that the content of four typical environmental estrogens in wter are still high.In addition, we investigated the degradation of BPA using the Dielectric Barrier Discharge(DBD) over water. Factors that influence the BPA mineralization efficiency, such as supporting voltage frequency, BPA initial concentration, pH and the electrical conductivity were evaluated at atmospheric pressure and room temperature. The results showed that above 80% degradation rate could be achieved at the initial BPA concentration 0.6481 mg·L-1 after 30 min treatment at different voltage frequency, The removal rate of BPA increased with decreasing the supporting voltage frequency. Meanwhile, the variation of electrical conductivity was large under low voltage frequency. In addition, initial concentration, pH value and the electrical conductivity also showed significant effect on BPA degradation.The degradation mechanism of BPA using DBD over water was analyzed by IC and GC-MS. The experimental results show that it is not only that the BPA was degraded, and the nitrogen in the air was transformed into the nitrate in the reaction solution by the UV and energy wave generated in the air-liquid interface, this leading to change the conductivity in solution. Because the content of BPA intermediates was very low, some of that can not reach the test condition, so the main intermediates can be determined in the degradation of BPA by DBD over water. There are trimethyl(4-nitrophenoxy)-silan, 2,5-di-tert-Butyl phenol, glycero and ethylene glycol.
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