Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
Department of Environmental Engineering, University of Patras, Seferi 2, 30100, Agrinio, Greece.
J Environ Manage. 2022 Oct 1;319:115719. doi: 10.1016/j.jenvman.2022.115719. Epub 2022 Jul 15.
Efficient and harmless disposal of landfill leachate has attracted increasing attention. In this study, the bio-electro-Fenton method was investigated and developed to degrade the organic compounds in landfill leachate by hydroxyl radical oxidation. The optimal operational parameters (i.e., pH and external voltage) of the bio-electro-Fenton system were detected. Under the conditions of pH 2, 0.6 V, the highest total chemical oxygen demand (COD) decrement efficiency was obtained (about 70%), with apparent removal constant at 6 h (k) of about 0.12 h. Subsequently, to further increase the degradation efficiency, functionalized carbon black and functionalized carbon nanotube (FCNT) were prepared as catalysts for the cathode electrode modification. With 0.4 mg/cm FCNT coated on the cathode electrode, 91.3% of the organic compounds were degraded, remaining only 84 mg/L COD (k = 0.24 h). In all the reactors, the COD was mainly decreased in 0-6 h, contributing to over 68% of the total degradation efficiency. In the bio-electro-Fenton system, the bio-anode electrode could enhance HO production and the conversion between Fe and Fe by strengthening electrons generation and transportation via the oxidation of organics by biofilms (dominant with Geobacter) covered on the carbon brush.
高效且无害的垃圾渗滤液处理方法引起了人们越来越多的关注。本研究采用生物电化学-Fenton 法，通过羟基自由基氧化降解垃圾渗滤液中的有机化合物。实验检测了生物电化学-Fenton 体系的最佳操作参数（即 pH 和外加电压）。在 pH 为 2、外加电压为 0.6 V 的条件下，总化学需氧量（COD）的去除效率最高（约 70%），6 h 时的表观去除常数（k）约为 0.12 h。随后，为进一步提高降解效率，制备了功能化炭黑和功能化碳纳米管（FCNT）作为阴极电极修饰催化剂。在阴极电极上涂覆 0.4 mg/cm 的 FCNT 后，91.3%的有机化合物被降解，仅剩余 84 mg/L 的 COD（k=0.24 h）。在所有反应器中，COD 主要在 0-6 h 内降低，对总降解效率的贡献率超过 68%。在生物电化学-Fenton 体系中，生物阳极电极可以通过生物膜（主要由 Geobacter 主导）对有机物的氧化作用增强电子的产生和传递，从而促进 HO 的产生和 Fe 与 Fe 的转化。
