文献类型：期刊文献

英文题名：Long-Term Removal of Cr(Vi) by Three Fe(0)-Prbs and the Corresponding Autotrophic and Heterotrophic Microbial Community Responses: The Influence of Sulfate and Nitrate

作者：Zhu, Yuling[1]; Liu, Yuxin[1]; Xia, Chuanjin[1]; Jia, Wanying[1]; He, Mengjiao[1]; Xu, Linfeng[1]

机构：[1] School of Life Science, Shaoxing University, Huancheng West Road 508, Shaoxing, 312000, China

年份：2023

外文期刊名：SSRN

收录：EI(收录号：20230035047)

语种：英文

外文关键词：Bacteria - Chromium compounds - Efficiency - Iron - Iron compounds - Organic carbon

外文摘要：Dissolved Cr(VI) removal by three commercially available Fe(0)-permeable reactive barriers (PRBs) was carried out in a column leaching experiment for 24 weeks in the presence and absence of SO42?, NO3?, and SO42?+NO3?. Changes in the contents of Cr(VI), TOC, SO42?/SO32?, and NO3?/NO2?/NH4+ in the aqueous solution, the valence state and bound state of Cr(VI), and the resulting microbial community structure in the solid phase were systematically determined. The PRB consisting of nano zero-valent iron (nZVI) showed the highest Cr(VI) removal efficiency, followed by ZVI and iron dust. Compared to the control, Cr(VI) removal in the three kinds of Fe(0)-based PRBs was enhanced by all the experimental conditions (SO42-, NO3-, and SO42-+NO3-). The promotional effect of each anion in descending order was SO42?+NO3- > SO42? > NO3-. The anion SO42- could attack the passive film on the surface of Fe(0) to release more electron donors, thereby supporting the growth of autotrophic microbes (Hydrogenophaga, Brevundimonas, Limnobacter, and Thauera), which transform HCO3- to organic carbon for utilization by heterotrophic strains (Pseudoxanthomonas and Arenimonas), ultimately resulting in higher Cr(VI) removal efficiency. NO3- accelerated the reduction of Cr(VI) via supplying nitrogen sources or electron receptors to autotrophic and heterotrophic bacteria (Hydrogenophaga, Brevundimonas, and Limnobacter, Arenimonas, and unclassified Rhizobiaceae). The boosting effect was enhanced in the combined presence of SO42- and NO3-. Our findings suggest that the combination of SO42?and NO3? is highly effective in stimulating the long-term Fe(0)-PRB efficiency over 24 weeks. ? 2023, The Authors. All rights reserved.