The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions, State Key Laboratory of Pulp and Paper Engineering, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China.
The Key Laboratory of Environmental Protection and Eco-Remediation of Guangdong Regular Higher Education Institutions, State Key Laboratory of Pulp and Paper Engineering, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China; Department of Plant and Environmental Sciences, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871, Frederiksberg C, Denmark.
Water Res. 2017 Oct 1;122:536-544. doi: 10.1016/j.watres.2017.05.043. Epub 2017 Jun 2.
In this study, Fe and mixed anaerobic culture were integrated in one column to investigate the coupled abiotic and biotic effects on hexa-valent chromium (Cr(VI)) removal and column longevity with an abiotic Fe column in the control experiments. According to the breakthrough study, a slower Cr(VI) breakthrough rate of 0.19 cm/PV was observed in the biotic Fe column whereas the value in the abiotic Fe column was 0.30 cm/PV, resulting in 64% longer life-span and 62% higher Cr(VI) removal capacity in the biotic Fe column than the abiotic one. The solid phase characterization by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) confirmed that this enhancement was attributed to the higher consumption of iron and greater production of diverse reactive minerals (e.g., green rust, magnetite and lepidocrocite) induced by the synergistic interaction of Fe and anaerobic culture, providing more reactive sites for Cr(VI) adsorption, reduction and co-precipitation. Furthermore, the decreasing breakthrough rates and growing iron corrosion along the biotic Fe column demonstrated an inhomogeneous distribution of reactive zones in the column and its latter 3/5 section was considered to be the most reactive area for Cr(VI) removal. These results indicate that the inoculation of microorganisms in Fe-based permeable reactive barriers will enable this technology a higher removal capacity and longer life-span for the remediation of Cr(VI)-contaminated groundwater.
在这项研究中，将铁和混合厌氧培养物集成在一个柱中，以研究非生物和生物因素对六价铬（Cr(VI)）去除和柱寿命的耦合作用，在对照实验中使用非生物铁柱。根据突破实验，在生物铁柱中观察到较慢的 Cr(VI)突破率为 0.19 cm/PV，而在非生物铁柱中的值为 0.30 cm/PV，导致生物铁柱的寿命延长 64%，Cr(VI)去除能力提高 62%。扫描电子显微镜（SEM）、能谱（EDX）和 X 射线衍射（XRD）的固相特征分析证实，这种增强归因于铁和厌氧培养物的协同作用导致铁的消耗更高，形成更多种类的反应性矿物（例如，绿锈、磁铁矿和水铁矿），为 Cr(VI)的吸附、还原和共沉淀提供了更多的反应性位点。此外，生物铁柱中突破率的降低和铁腐蚀的增加表明反应区在柱中的分布不均匀，其随后的 3/5 部分被认为是 Cr(VI)去除的最活跃区域。这些结果表明，在基于铁的可渗透反应屏障中接种微生物将使该技术具有更高的去除能力和更长的寿命，用于修复 Cr(VI)污染的地下水。
