Wang Yian, Zhang Xuehong, Lin Hua
College of Environmental Science and Engineering, Guilin University of Technology 319 Yanshan Street Guilin 541000 China
Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Areas, Guilin University of Technology 319 Yanshan Street Guilin 541000 China.
RSC Adv. 2022 May 17;12(24):15123-15132. doi: 10.1039/d2ra01828d.
Heavy metals and phenolic compounds existing in polluted wastewater are a threat to the environment and human safety. A downflow Swartz constructed wetland-microbial fuel cell (DLCW-MFC) was designed to treat polluted wastewater containing Cr(vi) and -chlorophenol (4-CP). To determine the effect of 4-CP concentration and hydraulic retention time (HRT) on the performance of the DLCW-MFC system, the wastewater purification, electricity generation, electrochemical performance, and growth status were studied. Addition of 17.9 mg L 4-CP improved the power density (72.04 mW m) and the charge transfer capacity (exchange current, 4.72 × 10 A) of DLCW-MFC. The removal rates of Cr(vi) and 4-CP at a 4-CP concentration of 17.9 mg L were 98.8% and 38.1%, respectively. The Cr content in was 17.66 mg/10 plants. However, a 4-CP concentration of 35.7 mg L inhibited the removal of Cr(vi) and the growth of , and decreased the electricity generation (2.5 mW m) as well as exchange current (1.21 × 10 A) of DLCW-MFC. An increase in power density and removal of Cr(vi) and 4-CP, along with an enhanced transport coefficient of , was observed with HRT. At an optimal HRT of 6.5 d, the power density, coulomb efficiency, and exchange current of DLCW-MFC were 72.25 mW m, 2.38%, and 4.99 × 10 A, respectively. The removal rates of Cr(vi) and 4-CP were 99.0% and 78.6%, respectively. The Cr content and transport coefficient of were 4.56 mg/10 plants and 0.451, respectively. Thus, DLCW-MFC is a promising technology that can be used to detoxify polluted wastewater containing composite mixtures and synchronously generate electricity.
污染废水中存在的重金属和酚类化合物对环境和人类安全构成威胁。设计了一种下行流施瓦茨人工湿地-微生物燃料电池（DLCW-MFC）来处理含有六价铬（Cr(vi)）和对氯苯酚（4-CP）的污染废水。为了确定4-CP浓度和水力停留时间（HRT）对DLCW-MFC系统性能的影响，研究了废水净化、发电、电化学性能以及植物生长状况。添加17.9 mg/L的4-CP提高了DLCW-MFC的功率密度（72.04 mW/m²）和电荷转移能力（交换电流，4.72×10⁻⁵ A）。在4-CP浓度为17.9 mg/L时，Cr(vi)和4-CP的去除率分别为98.8%和38.1%。植物中Cr含量为17.66 mg/10株。然而，4-CP浓度为35.7 mg/L时抑制了Cr(vi)的去除和植物生长，并降低了DLCW-MFC的发电量（2.5 mW/m²）以及交换电流（1.21×10⁻⁵ A）。随着HRT的增加，观察到功率密度以及Cr(vi)和4-CP的去除增加，同时植物的传输系数增强。在最佳HRT为6.5 d时，DLCW-MFC的功率密度、库仑效率和交换电流分别为72.25 mW/m²、2.38%和4.99×10⁻⁵ A。Cr(vi)和4-CP的去除率分别为99.0%和78.6%。植物的Cr含量和传输系数分别为4.56 mg/10株和0.451。因此，DLCW-MFC是一种有前途的技术，可用于对含有复合混合物的污染废水进行解毒并同步发电。
