Ren Jing, Li Haoxin, Li Na, Song Youtao, Chen Jiayi, Zhao Lin
School of Environment Sciences, Liaoning University Shenyang 110036 China.
Department of Environmental Science and Engineering, Tianjin University Tianjin 300072 China.
RSC Adv. 2020 May 1;10(29):17163-17170. doi: 10.1039/c9ra08538f. eCollection 2020 Apr 29.
Three-dimensional electrodes serve as more efficient cathodes for the generation of HO in microbial fuel cells (MFCs) than two-dimensional electrodes and possess significant electric potentials in the advanced oxidation of organics. In this study, we investigated the performance of a three-dimensional MFC-Fenton system in degrading -nitrophenol (PNP) in an aqueous solution with the objective of optimizing the operating parameters, including the initial pH, iron dosage, and loading resistance. A corresponding reaction pathway for PNP in the system was also proposed. The results showed that the three-dimensional electrode bioelectrochemical system efficiently oxidized PNP and removed total organic carbon over a short period (64 h). In addition, experiments showed that a lower initial pH enhanced the removal of PNP by the system. The highest removal efficiency of PNP was achieved with an initial iron concentration of 0.025 mol L, and a lower or higher iron concentration resulted in decreased PNP degradation. Furthermore, the treatment capacity of the system was remarkably enhanced at a low loading resistance of 20 Ω. Under optimal conditions, the three-dimensional MFC-Fenton system achieved 95.7% PNP removal (within 8 h). Furthermore, the system showed a stable high treatment efficiency of approximately 90% for low PNP concentrations in wastewater over as long as 96 h.
在微生物燃料电池（MFC）中，三维电极作为生成羟基自由基（HO）的阴极比二维电极更高效，并且在有机物的高级氧化过程中具有显著的电势。在本研究中，我们研究了三维MFC-芬顿系统在水溶液中降解对硝基苯酚（PNP）的性能，目的是优化操作参数，包括初始pH值、铁用量和负载电阻。还提出了该系统中PNP的相应反应途径。结果表明，三维电极生物电化学系统在短时间内（64小时）有效地氧化了PNP并去除了总有机碳。此外，实验表明较低的初始pH值提高了系统对PNP的去除率。初始铁浓度为0.025 mol/L时，PNP去除效率最高，铁浓度较低或较高都会导致PNP降解率下降。此外，在20Ω的低负载电阻下，系统的处理能力显著增强。在最佳条件下，三维MFC-芬顿系统在8小时内实现了95.7%的PNP去除率。此外，对于废水中低浓度的PNP，该系统在长达96小时的时间内表现出约90%的稳定高处理效率。
