Amen Mohamed Taha, Yasin Ahmed S, Hegazy Mohamed I, Jamal Mohammad Abu Hena Mostafa, Hong Seong-Tshool, Barakat Nasser A M
Bio-Nanosystem Engineering Department, Chonbuk National University, Jeonju 561-756, Republic of South Korea.
Microbiology Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt.
R Soc Open Sci. 2021 Nov 24;8(11):210996. doi: 10.1098/rsos.210996. eCollection 2021 Nov.
The possibility of using rainwater as a sustainable anolyte in an air-cathode microbial fuel cell (MFC) is investigated in this study. The results indicate that the proposed MFC can work within a wide temperature range (from 0 to 30°C) and under aerobic or anaerobic conditions. However, the rainwater season has a distinct impact. Under anaerobic conditions, the summer rainwater achieves a promised open circuit potential (OCP) of 553 ± 2 mV without addition of nutrients at the ambient temperature, while addition of nutrients leads to an increase in the cell voltage to 763 ± 3 and 588 ± 2 mV at 30°C and ambient temperature, respectively. The maximum OCP for the winter rainwater (492 ± 1.5 mV) is obtained when the reactor is exposed to the air (aerobic conditions) at ambient temperature. Furthermore, the winter rainwater MFC generates a maximum power output of 7 ± 0.1 mWm at a corresponding current density value of 44 ± 0.7 mAm at 30°C. While, at the ambient temperature, the maximum output power is obtained with the summer rainwater (7.2 ± 0.1 mWm at 26 ± 0.5 mAm). Moreover, investigation of the bacterial diversity indicates that spp. is the dominant electroactive genus in the summer rainwater, while in the winter rainwater, spp. is the main electroactive bacteria. The cyclic voltammetry analysis confirms that the electrons are delivered directly from the bacterial biofilm to the anode surface and without mediators. Overall, this study opens a new avenue for using a novel sustainable type of MFC derived from rainwater.
本研究探讨了在空气阴极微生物燃料电池（MFC）中使用雨水作为可持续阳极电解液的可能性。结果表明，所提出的MFC能够在较宽的温度范围（0至30°C）以及有氧或厌氧条件下工作。然而，雨水季节有明显影响。在厌氧条件下，夏季雨水在环境温度下不添加营养物质时可实现553±2 mV的理想开路电位（OCP），而添加营养物质会使电池电压在30°C和环境温度下分别增加到763±3 mV和588±2 mV。当反应器在环境温度下暴露于空气中（有氧条件）时，可获得冬季雨水的最大OCP（492±1.5 mV）。此外，冬季雨水MFC在30°C时对应的电流密度值为44±0.7 mA/m²时产生的最大功率输出为7±0.1 mW/m²。而在环境温度下，夏季雨水可获得最大输出功率（在26±0.5 mA/m²时为7.2±0.1 mW/m²）。此外，细菌多样性调查表明，夏季雨水中spp.是主要的电活性属，而在冬季雨水中，spp.是主要的电活性细菌。循环伏安法分析证实电子直接从细菌生物膜传递到阳极表面且无需媒介物。总体而言，本研究为使用源自雨水的新型可持续MFC开辟了一条新途径。
