Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science , Chinese Academy of Sciences , Nanjing 210008 , Jiangsu , China.
Civil and Environmental Engineering , University of California, Los Angeles , Los Angeles 90095 , California , United States.
Environ Sci Technol. 2019 Dec 17;53(24):14538-14547. doi: 10.1021/acs.est.9b04154. Epub 2019 Nov 22.
The use of bioaugmented zeolite (bio-zeolite) can be an effective technology for irreversibly removing recalcitrant organic pollutants in aqueous mixtures. Removal of 1,4-dioxane by a bio-zeolite ( CB1190-bioaugmented ZSM-5) in the presence of several chlorinated volatile organic compounds (CVOCs) was superior to removal by adsorption using abiotic zeolite. Mixtures containing 1,1-dichloroethene (1,1-DCE) were an exception, which completely inhibited the bio-zeolite system. Specific adsorption characteristics were studied using adsorption isotherms in single-solute and bisolute systems accompanied by Polanyi theory-based Dubinin-Astakhov (DA) modeling. Adsorption behavior was examined using characteristic energy () from modified DA models and molecular dynamics simulations. While the tight-fit of 1,4-dioxane in the hydrophobic channels of ZSM-5 appears to drive 1,4-dioxane adsorption, the greater hydrophobicity of trichloroethene and -1,2-dichloroethene cause them have a greater affinity over 1,4-dioxane for adsorption sites on the zeolite. 1,4-Dioxane was desorbed and displaced by CVOCs except 1,1-DCE because of its low value, explaining why bio-zeolite only biodegraded 1,4-dioxane in 1,1-DCE-free CVOC mixtures. Understanding the adsorption mechanisms of solutes in complex mixtures is crucial for the implementation of sorption-based treatment technologies for the removal of complex contaminant mixtures from aquatic environments.
生物增强沸石（bio-zeolite）的使用可以是一种有效技术，用于不可逆地去除水混合物中的难降解有机污染物。在存在几种氯化挥发性有机化合物（CVOCs）的情况下，生物沸石（CB1190-生物增强 ZSM-5）对 1,4-二恶烷的去除优于使用非生物沸石的吸附去除。含有 1,1-二氯乙烯（1,1-DCE）的混合物是一个例外，它完全抑制了生物沸石系统。使用单溶质和双溶质系统中的吸附等温线以及基于 Polanyi 理论的 Dubinin-Astakhov (DA) 模型研究了特定的吸附特性。使用从改进的 DA 模型和分子动力学模拟获得的特征能量 () 来检查吸附行为。虽然 1,4-二恶烷在 ZSM-5 的疏水通道中的紧密拟合似乎驱动了 1,4-二恶烷的吸附，但三氯乙烯和 -1,2-二氯乙烯的较大疏水性导致它们对沸石上的吸附位点具有比 1,4-二恶烷更大的亲和力。由于 1,1-DCE 的 值较低，1,4-二恶烷被 CVOC 解吸和取代，这解释了为什么生物沸石仅在不含 1,1-DCE 的 CVOC 混合物中生物降解 1,4-二恶烷。了解复杂混合物中溶质的吸附机制对于实施基于吸附的处理技术从水生环境中去除复杂污染物混合物至关重要。
