Enhanced nitrate removal and high selectivity towards dinitrogen for groundwater remediation using biochar-supported nano zero-valent iron
Enhanced nitrate removal and high selectivity towards dinitrogen for groundwater remediation using biochar-supported nano zero-valent iron
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使用生物炭支撑的纳米零价铁增强地下水修复中的硝酸盐去除率和对二氮的高选择性
DOI：
10.1016/j.cej.2018.07.127
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发表时间：
2018-12
影响因子：
15.1
通讯作者：
Yu Xiangyang
中科院分区：
文献类型：
--
作者：
Wei Anlei;Ma Jing;Chen Jingjing;Zhang Yan;Song Jinxi;Yu Xiangyang
我们制备了纳米零价铁/生物炭复合材料（nZVI/BC），以无害产品去除地下水中的硝酸盐。结果表明，不同Fe(0)与生物炭质量比的nZVI/BC表现出不同的硝酸盐去除效率，质量比为1:2的nZVI/BC具有最佳的硝酸盐去除率。 nZVI/BC 在 2-12 的宽 pH 范围内保持了较好的硝酸盐去除率 (75.0%-97.0%)。当初始硝酸盐浓度超过40mg/L时，由于nZVI/BC表面严重腐蚀和堵塞，硝酸盐去除量下降。硝酸盐去除过程遵循一级动力学反应。就真实地下水而言，nZVI/BC 比纯 Fe(0) 纳米颗粒和生物炭去除了更多的硝酸盐。反应产物分析显示，60.1% 的去除硝酸盐选择性地变成二氮。 X射线光电子能谱测量表明，硝酸盐氧化的Fe(0)导致nZVI/BC表面磁铁矿的显着增加。长时间反应的氧化还原电位和pH值分别在-210mV和8-9左右变化。这些变化促进了硝酸盐选择性还原为二氮。我们还提出，生物炭可以通过直接介导氧化还原电位、pH 和电子转移来为硝酸盐还原提供有利的环境，这为增强去除和选择性还原硝酸盐建立了可能的机制。我们的研究表明，nZVI/BC 将是修复受硝酸盐污染的地下水的一种有前途的替代方案。
We prepared nano zero-valent iron/biochar composites (nZVI/BC) to remove nitrate from groundwater with harmless products. Results show nZVI/BCs derived from different mass ratios of Fe(0) to biochar exhibited different nitrate removal efficiencies, and the mass ratio of 1:2 developed the nZVI/BC with optimum nitrate removal. The nZVI/BC maintained preferable nitrate removal (75.0%–97.0%) over a wide pH range 2–12. Nitrate removal amount declined due to serious corrosion and clogging of nZVI/BC’s surface when initial nitrate concentration exceeded 40 mg/L. The nitrate removal process followed a first-order kinetic reaction. As regards real groundwater, the nZVI/BC removed more nitrate than both pure Fe(0) nanoparticles and biochar. Reaction product analysis revealed 60.1% of removed nitrate selectively became dinitrogen. X-ray photoelectron spectroscopy measurements suggested that nitrate-oxidized Fe(0) resulted in significant increase of magnetite on the surface of nZVI/BC. The redox potential and pH of long duration in reaction changed around −210 mV and 8–9, respectively. These changes facilitated the selective reduction of nitrate to dinitrogen. We also proposed that biochar may provide favorable circumstances for nitrate reduction by directly mediating redox potential, pH and electron transfer, which establishes a possible mechanism for the enhanced removal and selective reduction of nitrate. Our study suggests that nZVI/BC would be a promising alternative for the remediation of nitrate-contaminated groundwater.
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DOI：
10.1007/s00128-016-1865-9
发表时间：
2017-03
影响因子：
2.7
作者：
G. Vilardi;L. Di Palma
通讯作者：
G. Vilardi;L. Di Palma
影响因子：
12.8
作者：
D. P. Siantar;C. Schreier;C. Chou;M. Reinhard
通讯作者：
D. P. Siantar;C. Schreier;C. Chou;M. Reinhard
H2O2/HCl 预处理提高零价铁的还原性能：硝酸盐还原案例研究
影响因子：
15.1
作者：
Zhe Yang;Chao Shan;Yuchen Mei;Zhao Jiang;Xiaohong Guan;Bingcai Pan
通讯作者：
Bingcai Pan
影响因子：
11.4
作者：
Alowitz, MJ;Scherer, MM
通讯作者：
Scherer, MM
影响因子：
22.1
作者：
Jung, Junyoung;Bae, Sungjun;Lee, Woojin
通讯作者：
Lee, Woojin