Department of Crop and Soil Environmental Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States.
Department of Crop and Soil Environmental Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States.
Chemosphere. 2019 Jun;224:480-486. doi: 10.1016/j.chemosphere.2019.02.150. Epub 2019 Feb 23.
Estrogens are of environmental concern because disruptive effect on biological functions at levels as low as ng/L. Wastewater treatment plant effluent is a significant source of estrogens in aquatic environment. Ferric ions (Fe)-saturated montmorillonite has been shown to effectively remove 17β-estradiol (βE2), a common estrogen, from pure water by catalyzing formation of insoluble βE2 oligomers on mineral surfaces. We investigated the effects of reaction temperature, dissolved organic matter, pH, and common cations, on Fe-saturated montmorillonite-surface catalyzed βE2 polymerization, and the removal of this estrogen from three different secondary wastewater effluents with more complicated matrixes. Highest βE2 removal occurred at near neutral pH and it increased with increasing treatment temperatures. Presence of common cations in the water did not affect the reaction efficiency. Dissolved organic matter at 15 mg C/L slightly lowered the βE2 removal efficiency as compared to that in pure water. Regardless of the source of wastewater effluents, βE2 removal efficiency of ∼40% was achieved using the dosage of Fe-saturated montmorillonite similar to that tested for the aqueous phases with simpler matrix. Doubling this dosage resulted in removal of ∼80% of βE2 from a tested secondary wastewater effluent within 30 min reaction. For wastewater with complex matrixes at the commonly reported βE2 levels which are magnitudes lower than the tested concentration in our study, this dosage would provide sufficient available reaction sites for the surface-catalyzed βE2 polymerization. This study demonstrated that Fe-saturated montmorillonite is a promising material for effective removal of phenolic estrogen compounds from domestic wastewater effluents.
雌激素是环境关注的问题，因为它们在纳克/升（ng/L）的低水平就可能对生物功能产生干扰效应。污水处理厂的废水是水生环境中雌激素的重要来源。已经证明，铁离子（Fe）饱和蒙脱石通过在矿物表面催化形成不溶性βE2低聚物，可有效去除水中的 17β-雌二醇（βE2），这是一种常见的雌激素。我们研究了反应温度、溶解有机物、pH 值和常见阳离子对 Fe 饱和蒙脱石表面催化βE2聚合以及从具有更复杂基质的三种不同二级废水处理厂废水中去除这种雌激素的影响。在近中性 pH 值下，βE2 的去除效率最高，并且随着处理温度的升高而增加。水中常见阳离子的存在并不影响反应效率。与纯水中相比，15mgC/L 的溶解有机物略微降低了βE2 的去除效率。无论废水来源如何，使用与测试较简单基质的水相相似的剂量的 Fe 饱和蒙脱石，即可实现约 40%的βE2 去除效率。将该剂量增加一倍，可在 30min 反应内将测试的二级废水处理厂废水中约 80%的βE2 去除。对于通常报道的βE2 浓度低于本研究中测试浓度的复杂基质废水，该剂量可为表面催化βE2聚合提供足够的可用反应位点。本研究表明，Fe 饱和蒙脱石是一种从生活污水中有效去除酚类雌激素化合物的有前途的材料。
