Hu Jia-Ping, Zeng Cui-Ping, Luo Hai-Ping, Liu Guang-Li, Zhang Ren-Duo, Lu Yao-Bin
Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
Huan Jing Ke Xue. 2019 Jan 8;40(1):327-335. doi: 10.13227/j.hjkx.201806171.
The removal efficiencies of environmental pollutants in a microbial electrolysis system (MES) with a biocathode are highly affected by the externally applied voltage. Although the cathode biofilm plays a key role in the pollution removal, its response to the applied voltage is still unknown. A two-chambered MES with a biocathode was constructed to study the impact of the different applied voltages (0.4, 0.5, 0.6, 0.7, and 0.8 V) on the sulfate reduction, extracellular polymer formation, and cathodic bacterial community. The results show that the current output and coulomb and COD removals of the MES are positively correlated with the applied voltage ranging from 0.4 to 0.8 V. The sulfate reduction rate first increases and then decreases with increasing voltage in the MES. The maximum sulfate reductive rate[78.9 g·(m·d)] and maximum S production (31.9 mg·L±2.2 mg·L) were achieved at 0.7 V. The highest electron recovery efficiencies of the MES are 41.8%; hydrogen production may be a pathway leading to electron loss. The polysaccharide and protein contents of the cathode biofilm increase with increasing voltage. The cathode biomass at 0.8 V is 70% higher than that at 0.4 V. The high throughput sequencing results show that Proteobacteria and are dominant in the cathodic microbial community at the phylum and genus levels, respectively. The relative abundance of shows little variation with the increasing voltage, indicating that is of advantage for using the cathode as electron donor for the respiratory metabolism. With the increasing voltage, the distribution of at species level indicates that the changes of RS-1 and s_unclassified_g_ are contrary.
具有生物阴极的微生物电解系统（MES）中环境污染物的去除效率受外部施加电压的影响很大。尽管阴极生物膜在污染物去除中起关键作用，但其对施加电压的响应仍不清楚。构建了一个具有生物阴极的双室MES，以研究不同施加电压（0.4、0.5、0.6、0.7和0.8 V）对硫酸盐还原、胞外聚合物形成和阴极细菌群落的影响。结果表明，MES的电流输出、库仑和COD去除量与0.4至0.8 V的施加电压呈正相关。MES中硫酸盐还原率随电压升高先增加后降低。在0.7 V时实现了最大硫酸盐还原率[78.9 g·(m·d)]和最大S产量（31.9 mg·L±2.2 mg·L）。MES的最高电子回收效率为4l.8%；产氢可能是导致电子损失的一条途径。阴极生物膜的多糖和蛋白质含量随电压升高而增加。0.8 V时的阴极生物量比0.4 V时高70%。高通量测序结果表明，变形菌门和[此处原文缺失具体属名]分别在阴极微生物群落的门和属水平上占主导地位。[此处原文缺失具体属名]的相对丰度随电压升高变化不大，表明[此处原文缺失具体属名]有利于将阴极作为呼吸代谢的电子供体。随着电压升高，物种水平上[此处原文缺失具体属名]的分布表明[此处原文缺失具体种名]RS - 1和s_unclassified_g_的变化相反。
