Zero valent iron as an electron-donor for methanogenesis and sulfate reduction in anaerobic sludge
Zero valent iron as an electron-donor for methanogenesis and sulfate reduction in anaerobic sludge
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DOI：
10.1002/bit.20623
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发表时间：
2005-12-30
影响因子：
3.8
通讯作者：
Field, JA
中科院分区：
文献类型：
--
作者：
Karri, S;Sierra-Alvarez, R;Field, JA
零价铁（ZVI）是一种常用于可渗透反应屏障（PRB）的反应介质。硫酸盐还原菌正被考虑用于PRB中重金属的固定化。本研究的目的是评估ZVI作为电子供体的硫酸盐还原在自然混合厌氧培养的潜力。还探索了产甲烷菌利用ZVI作为电子供体的能力，因为这些微生物经常与硫酸盐还原剂竞争共同底物。以厌氧生物反应器污泥为接种物，比较了4种不同粒径（1.120，0.149，0.044和0.010 mm）的ZVI作为电子供体的效果。在缺乏硫酸盐的矿物介质中评价甲烷生成。在含有硫酸盐和特定产甲烷抑制剂2-溴乙烷磺酸盐的矿物介质中评价硫酸盐还原。与内源性底物对照相比，ZVI促进了甲烷产量和硫酸盐还原的显着增加。甲烷形成或硫酸盐还原的速率与ZVI的表面积正相关。最高速率为0.310 mmol CH 4/mol Fe（0.）d和0.804 mmol SO 42-还原态/mol Fe（0.）用最细等级的ZVI（0.01 mm）获得了10天的时间。结果表明，ZVI是很容易利用作为一个缓慢释放的电子供体在厌氧污泥产甲烷和硫酸盐还原，因此，在生物修复应用中有很好的潜力。(c)2005 Wiley Periodicals，Inc.
Zero valent iron (ZVI) is a reactive media commonly utilized in permeable reactive barriers (PRBs). Sulfate reducing bacteria are being considered for the immobilization of heavy metals in PRBs. The purpose of this study was to evaluate the potential of ZVI as an electron donor for sulfate reduction in natural mixed anaerobic cultures. The ability of methanogens to utilize ZVI as an electron-donor was also explored since these microorganisms often compete with sulfate reducers for common substrates. Four grades of ZVI of different particle sizes (1.120,0.149, 0.044, and 0.010 mm diameter) were compared as electron donor in batch bioassays inoculated with anaerobic bioreactor sludge. Methanogenesis was evaluated in mineral media lacking sulfate. Sulfate reduction was evaluated in mineral media containing sulfate and the specific methanogenic inhibitor, 2-bromoethane sulfonate. ZVI contributed to significant increases in methane production and sulfate reduction-compared to endogenous substrate controls. The rates of methane formation or sulfate reduction were positively correlated with the surface area of ZVI. The highest rates of 0.310 mmol CH4 formed/mol Fe(0.)day and 0.804 mmol SO42- reduced/mol Fe(0.)day were obtained with the finest grade of ZVI (0.01 mm). The results demonstrate that ZVI is readily utilized as a slow-release electron donor for methanogenesis and sulfate reduction in anaerobic sludge; and therefore, has a promising potential in bioremediation applications. (c) 2005 Wiley Periodicals, Inc.