作者：Wang, Q (Wang, Qing); Song, X (Song, Xin); Tang, SY (Tang, Shiyue) ; Yu, L (Yu, Lei)

题目：Enhanced removal of tetrachloroethylene from aqueous solutions by biodegradation coupled with nZVI modified by layered double hydroxide

刊物：CHEMOSPHERE，卷: 243  文献号: UNSP 125260

DOI: 10.1016/j.chemosphere.2019.125260

出版年: MAR 2020

下载：https://www.sciencedirect.com/science/article/pii/S0045653519325007?via%3Dihub

摘要：

Chlorinated volatile organic compounds, such as tetrachloroethylene (PCE), are the most commonly detected toxic contaminants in groundwater. In this study, the performance of PCE removal by a microbial consortium combined with nZVI modified by layered double hydroxide (nZVI-LDH) was evaluated. The enriched PCE-degrading consortium consisted of 44.49% Clostridium and other potential PCE degraders, and 0.5-2.5 mg/L PCE was completely biodegraded within 4 days. The characterization of nZVI-LDH indicated that LDH was coated on the surfaces of nZVI particles with an increased surface area. The PCE removal kinetics by nZVI-LDH was well described by a second-order model, and the removal rate constant of nZVI-LDH was 0.12 Lh/mg, higher than that of native nZVI (0.02 Lh/mg). Interestingly, the presence of Cu2+ improved the removal efficiency of PCE by nZVI-LDH, owing to its role as a catalyst or medium for charge transfer during reduction. Removal of PCE was enhanced by coupling the PCEdegrading consortium and nZVI-LDH. The initial removal of PCE was mainly dominated by the abiotic degradation and adsorption of nZVI-LDH, and biodegradation then played a major role in the exhaustion of nZVI-LDH. These results suggest that biodegradation coupled with nZVI-LDH has a great potential for applications in the remediation of chlorinated-solvent contaminated groundwater. (C) 2019 Elsevier Ltd. All rights reserved.