| Environmental endocrine disrupters, or named as environmental hormones, are defined as exogenous substances that interfere with the synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body that are responsible for the maintenance of homeostasis, reproduction, development, and behavior. Environmental endocrine disrupters (EEDs) mainly come from natural sources and artifical chemicals. It has been demonstrated that EEDs are related to reproductive difficulty, abnormal development and some disease of immune and nervous system. Researches on the degradation behavior in the environment and treatment method development are the two important aspects for EEDs study. At present, the study on transport, transform and fate of environmental endocrine disrupters are very important in this field.In our work, 17a-ethynylestradiol (EE2), 4-nonylphenol (NP), and bisphenol-A (BPA) were used as representative environmental endocrine disruptors and the photodegradation of them in aqueous solution with algae and relative mechanism were studied for the first time. This research will provide the reference for predicting the photodegradation of environmental endocrine disruptors in the real environment. Used algae were Nitzschia hantzschiana, Chlorella vulgaris, Anabaena cylindrica, Microcystis aeruginosa. High-pressure mercury lamp ( 313 nm) and UV light ( =254 nm) were used as light sources. Photochemical reactions experiments were performed in a concentric reactor or other. At different time intervals during the irradiation, the concentrations of environmental endocrine disruptors were analyzed using fluorescence spectroscopy or high-pressure liquid chromatography (HPLC). The kinetics analyses of the photodegradation reaction were performed ?According to the first study on the photoproduction of -OH in algae solution under light and the identification of photodegradation products of 17a-ethynylestradiol (EE2), the mechanism of the photodegradation of EE2 in aqueous solution with algae was proposed. The photochemical degradation of EE2 was enhanced due to the -OH addition (photooxidation), etc.Main contents, results, and conclusions of this dissertation are as follows.1. The photolysis of 17 -ethynylestradiol (EE2) or 17 -estradiol (E2) in aqueous solution under irradiation of 250W high-pressure mercury lamp or UV light was studied. Also, kinetics analysis of the photodegradation was carried out. The effects of Fe(III), pH, light sources, light intensity, and exposure time (0 on photolysis were studied. The photodegradation could be enhanced by Fe(III) added. pH had effect on the photodegradation. The photolysis was more efficient under irradiation of UV light than that under 250W high-pressure mercury lamp and the UV light-induced photolysis reaction should be pseudo-first order (ln(c/c0)=kt).2. The photodegradation of 17 -ethynylestradiol(EE2) in an aqueous solution with algae (such as Anabaena cylindrica, Nitzschia hantzschiana, Chlorella vulgaris, etc.) under 250W high-pressure mercury lamp was investigated for the first time. The exposure time was 4 h. Also, related kinetics of the photodegradation was studied. The affecting factors of the photodegradation were studied in detail, such as initial EE2 concentration, algae concentration, Fe(III), exposure time(t), etc. The results showed that EE2 photodegradation increased with algae concentration increasing. According to the results of kinetic analyses, the kinetic equation of EE2 photodegradation in aqueous solution with algae under 250W HPML should be pseudo-first order. Also the experiments to study the photodegradation of 5.0 mg/L nonylphenol and 5.0 mg/L bisphenol A in algae solution were carried out. The results showed that algae could enhance the photodegradation of them. The experiments to study the photodegradation of EE2 in the binary or ternary system consisted of N. hantzschiana, HA, and Fe(III) were carried out. The comparison of results showed that the removal efficiency of EE2 in binary or ternary system under 250W HPML...
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