School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, China.
School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, China.
Sci Total Environ. 2019 Jul 15;674:336-343. doi: 10.1016/j.scitotenv.2019.04.206. Epub 2019 Apr 15.
This study aimed to enhance treatment of wastewater containing nitrobenzene (NB) and sulfate using biocathode enriched with sulfate-reducing bacteria in microbial electrolysis cell (MEC). Artificial wastewater with 50 mg L NB and 200 mg L sulfate was used as the catholyte. With 0.8 V applied voltage, removal efficiencies of NB and sulfate reached 98% and 34%, respectively, within 36 h. Aniline and sulfide were the main reductive products in the catholyte with concentrations increased to 0.32 and 0.51 mM, which accounted for 97% and 78% of the removed NB and sulfate, respectively. Sulfate-reducer Desulfovibrio sp. and Wolinella sp. played the dominant role in the biocathode for the reductions of sulfate and NB. Analyses of scanning electron microscope and X-ray photoelectron spectroscopy showed the formation of elemental S on the biocathode surface. The relative abundance of sulfur-oxidizing bacterium Thioclava sp. reached 24% on the biocathode. The results indicated that the oxidation process from S to S occurred on the biocathode, which provided electrons to biofilm for NB reduction. The MEC with sulfate-reducer enriched biocathode can be used as an alternative to treat complex wastewater containing NB and sulfate.
本研究旨在利用微生物电解池（MEC）中富含硫酸盐还原菌的生物阴极来增强对含硝基苯（NB）和硫酸盐废水的处理。以 50mg/L NB 和 200mg/L 硫酸盐的人工废水作为阴极液。在 0.8V 的外加电压下，NB 和硫酸盐的去除效率分别在 36h 内达到 98%和 34%。苯胺和硫化物是阴极液中的主要还原产物，浓度分别增加到 0.32 和 0.51mM，分别占去除的 NB 和硫酸盐的 97%和 78%。硫酸盐还原菌脱硫弧菌属和沃林氏菌属在生物阴极中对硫酸盐和 NB 的还原起主要作用。扫描电子显微镜和 X 射线光电子能谱分析表明，生物阴极表面形成了元素硫。硫氧化菌 Thioclava sp. 的相对丰度在生物阴极上达到 24%。结果表明，生物阴极上发生了从 S 到 S 的氧化过程，为 NB 还原向生物膜提供了电子。富含硫酸盐还原菌的 MEC 可作为处理含有 NB 和硫酸盐的复杂废水的替代方法。
