School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China.
School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, China; SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, School of Environment, South China Normal University, Guangzhou 510006, China.
Sci Total Environ. 2023 Feb 10;859(Pt 1):160131. doi: 10.1016/j.scitotenv.2022.160131. Epub 2022 Nov 11.
Microbial electrochemical system (MES) is an emerging wastewater treatment technology that compensates the energy demands of containments removal by in situ converting the chemical energy of organic pollutants. As the structure for exoelectrogens and the reaction site of extracellular electron transfer (EET), the anode is essential for MES. The future commercial application of MES requires efficiency and large-scale fabrication available anode. In this study, a 3D anode with millimeter-scale pores (3D-MPA) was successfully constructed by sacrificial template method, with low-cost phenolic resin as carbon precursor and polymethyl methacrylate (PMMA) pellets as template. With customized and ordered pore of 1 mm, the 3D-MPAs allowed the microorganisms to colonize inside, improving anodic space utilization efficiency. Different carbonization temperature in tested range from 700 °C to 1000 °C regulated the micrometer-scale convex structures and surface roughness of 3D-MPAs, causing electrochemical performance changes. The 3D-MPA-900 obtained the largest electroactive surface area (102 ± 4.1 cm) and smallest ohmic resistance (1.8 ± 0.09 Ω). Equipped with MES, 3D-MPA-900 reached the highest power density and current density (2590 ± 25 mW m and 5.20 ± 0.07 A m). Among tested 3D-MPA, the excellent performance of 3D-MPA-900 might be attributed by its convex structures with suitable size and surface coverage. The surface roughness of 3D-MPA-900 enhanced the microorganism adherence, which then promoted EET on anode surface. Generally, phenolic-based 3D-MPA made of sacrificial-template method had controllable porous structure, large-scale fabrication availability, high chemical stability and excellent mechanical property, which could be promising for the commercial application of MES.
微生物电化学系统（MES）是一种新兴的废水处理技术，通过原位转化有机污染物的化学能来补偿去除污染物所需的能量。作为产电微生物的结构和细胞外电子传递（EET）的反应位点，阳极对于 MES 至关重要。MES 的未来商业应用需要高效率和大规模制造的可用阳极。在这项研究中，通过牺牲模板法成功构建了具有毫米级孔（3D-MPA）的 3D 阳极，以低成本酚醛树脂为碳前体，以聚甲基丙烯酸甲酯（PMMA）球为模板。具有定制的和有序的 1 毫米孔，3D-MPAs 允许微生物在内部定植，提高了阳极空间的利用效率。测试范围内不同的碳化温度（700°C 至 1000°C）调节了 3D-MPAs 的微米级凸状结构和表面粗糙度，导致电化学性能发生变化。3D-MPA-900 获得了最大的电化学活性表面积（102±4.1cm）和最小的欧姆电阻（1.8±0.09Ω）。配备 MES 后，3D-MPA-900 达到了最高的功率密度和电流密度（2590±25mWm 和 5.20±0.07Am）。在测试的 3D-MPA 中，3D-MPA-900 的优异性能可能归因于其具有适当尺寸和表面覆盖率的凸状结构。3D-MPA-900 的表面粗糙度增强了微生物的附着，从而促进了阳极表面的 EET。一般来说，基于酚醛的 3D-MPA 采用牺牲模板法制造，具有可控的多孔结构、大规模制造的可用性、高化学稳定性和优异的机械性能，有望在 MES 的商业应用中得到应用。
