| Bisphenol A (BPA) is an indispensable organic chemical for production of polycarbonate, epoxide resin, flame retardant, plasticizer and many other plastic products. BPA enters the aqueous body and soil mainly by emission during the process of manufacturing, transportation and use. BPA has been blacklisted in many countries as it has the horrible endocrine disruption effect on reproductive system, which is similar to the estrogenic effects of natural estrogens e.g. estrone (E1),17β-estradiol (E2), estriol (E3) and17α-ethynylestradiol (EE2). In addition, with the development of large-scale and intensive livestock, more and more animal farm wastewater, with E1, E2, E3and EE2together, have been discharged into surface water directly without any treatment, which poses a great potential threat to ecological environment and human health. For the commonly detection and estrogenic effect, the estrogens abovementioned have been attracted great attentions. Therefore, the adsorption/desorption, biodegradation, transportation and transformation etc. have already been become one of the most hot issues in the field of environmental pollution control chemistry.Less study on the method of determination trace level of estrogens in aqueous and adsorption behavior of estrogens in soil/water system was investigated, as well as the biodegradation and absorbed immobilization of estrogens. Hence, E1, E2, EE2, E3and BPA were chosen as typical estrogenic contaminants, the methods for determination of trace level estrogens based on dispersive liquid liquid microextraction and high performance liquid chromatography were systematically investigated, the adsorption behavior of estrogens in water/soil system was analyzed particularly, the enhancement of biodegradation of estrogens using pseudomonas putida with the help of glucose, peptone and ultrasonic assistive technologies were explored, and the absorbed immobilization of estrogens by soil spiked with additive were researched as well. The results of this study provide useful information for controlled transport of estrogens and bioremediation enhancement technology.Non-random two liquid equation was applied to correlate the experimental data in this paper, and the molecular interaction energy followed the order of EE2>BPA>E1>E2>E3. It should be noted that the partition coefficients of estrogens between [C6MIM]PF6and water phase were twice more than that between traditional extractant and water phase,[C6MIM]PF6was the alternative for extraction of estrogens from aqueous phase.Based on the dispersive liquid liquid microextraction and high performance liquid chromatography (HPLC), the analytical methods for determination of trace level estrogens in water were developed, and the established methods were evaluated in terms of the linear range, limit of detection, precision and accuracy, matrix effect and so on. The limit of detection of the methods could be below ppb, and had some advantages such as simple operation, low cost, environmental friendly and saving-time.The adsorption kinetics and thermodynamics of estrogens in soil were discussed using batch experiment. Adsorption of estrogens on soil consisted of two processes of quick adsorption and slow adsorption, and reached a state of equilibrium in24h. Both Langmuir and Flundlich isotherms could describe the adsorption thermodynamic behavior. The experimental results showed that competitive adsorption was occurred when coexistence of estrogens and higher hydrophobicity of estrogen could promote lower hydrophobicity of estrogen adsorption on soil. The negative values of adsorption enthalpy and sorption entropy of estrogens indicated that the overall adsorption processes are exothermic in nature. The modulus of free energy of adsorption value is less than40kJ/mol, which implied that the adsorption mechanisms of estrogens are dominated by physical adsorption.Additionally, under the external carbon source-glucose, nitrogen addition-peptone, and ultrasonic assistive technologies conditions, pseudomonas putida was selected to degrade estrogens in the paper. The enhancement effects of factors mentioned above on the biodegradation were studied. Glucose prompted the biodegradation efficiency in the form of cometabolic degradation, and the removal rates of E1, E2, EE2, E3and BPA were1.6times,1.2times,1.2times,2.0times and1.3times of that without addition of glucose; peptone provided nitrogen and suitable pH for micrograms, and increased the removal rates of E1, E2, EE2to above90%, the removal rates of E3and BPA were more than60%and82%, which were2.0times and1.4times of that without addition of peptone, respectively. The removal rates of E1, E2, EE2and BPA increased more than90%, and the E3increased to60%in10.0min with the help of ultrasonic assistive technology.Finally, MnO2, humic acids, montmorillonite and Fe3O4were employed to enhance the estrogens adsorption onto the soil. The experimental results of desorption showed the all of the additives could obviously reduce the desorption quantity and realize the immobilization of estrogens in soil, keeping the water body free from pollution. The immobilized results followed the order of MnO2> Fe3O4> montmorillonite> humic acids; however, the immobilization of E1by Fe3O4was not significant. Moreover, from molecular response using FTIR spectroscopy, it can be known that the enhanced effect of the additive on the estrogens adsorbed onto soil were contributed mainly by the hydrogen bonding association, partition, and surface adsorption as well.
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