Microbial fuel cells (MFCs) have been widely investigated for organic-based waste/substrate conversion to electricity. However, toxic compounds such as heavy metals are ubiquitous in organic waste and wastewater. In this work, a sulfate reducing bacteria (SRB)-enriched anode is used to study the impact of Cu²⁺ on MFC performance. This study demonstrates that MFC performance is slightly enhanced at concentrations of up to 20 mg/L of Cu²⁺, owing to the stimulating effect of metals on biological reactions. Cu²⁺ removal involves the precipitation of metalloids out of the solution, as metal sulfide, after they react with the sulfide produced by SRB. Simultaneous power generation of 224.1 mW/m² at lactate COD/SO₄²⁻ mass ratio of 2.0 and Cu²⁺ of 20 mg/L, and high Cu²⁺ removal efficiency, at >98%, are demonstrated in the anodic chamber of a dual-chamber MFC. Consistent MFC performance at 20 mg/L of Cu²⁺ for ten successive cycles shows the excellent reproducibility of this system. In addition, total organic content and sulfate removal efficiencies greater than 85% and 70%, respectively, are achieved up to 20 mg/L of Cu²⁺ in 48 h batches. However, higher metal concentration and very low pH at <4.0 inhibit the SRB MFC system. Microbial community analysis reveals that Desulfovibrio is the most abundant SRB in anode biofilm at the genus level, at 38.1%. The experimental results demonstrate that biological treatment of low-concentration metal-containing wastewater with SRB in MFCs can be an attractive technique for the bioremediation of this type of medium with simultaneous energy generation.

中文翻译：

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混合硫酸盐还原菌富集的微生物燃料电池，用于处理含铜废水

微生物燃料电池（MFCs）已被广泛研究用于将有机废物/底物转化为电能。但是，有机废物和废水中普遍存在有毒化合物，例如重金属。在这项工作中，使用富含硫酸盐还原细菌（SRB）的阳极来研究Cu ²⁺对MFC性能的影响。这项研究表明，由于金属对生物反应的刺激作用，在高达20 mg / L的Cu ²⁺浓度下，MFC的性能略有提高。Cu ^2+的去除涉及在与SRB生成的硫化物反应后，作为金属硫化物的类金属从溶液中沉淀出来。乳酸COD / SO _4时同时发电224.1 mW / m ²在双室MFC的阳极室中，证明了^2-的质量比为2.0，Cu ²⁺为20 mg / L，以及高的Cu ²⁺去除效率（> 98％）。MFC在20 mg / L的Cu ^2+下连续10个连续循环的性能稳定，表明该系统具有出色的重现性。此外，在48小时内，Cu ^2+的总有机含量和硫酸盐去除率分别达到85％和70％以上，达到20 mg / L。但是，较高的金属浓度和<4.0的非常低的pH值会抑制SRB MFC系统。微生物群落分析表明，脱硫弧菌在属水平上是阳极生物膜中最丰富的SRB，为38.1％。实验结果表明，在MFC中用SRB对低浓度含金属废水进行生物处理可能是一种有吸引力的技术，可以同时修复这种类型的介质并产生能量。