Efficient degradation of organic compounds in landfill leachate via developing bio-electro-Fenton process

Ziyi Yang; Shimin Wu; Hangyu Sun; Samuel Gyebi Arhin; Vagelis G Papadakis; Maria A Goula; Guangqing Liu; Yi Zhang; Ling Zhou; Wen Wang

doi:10.1016/j.jenvman.2022.115719

Efficient degradation of organic compounds in landfill leachate via developing bio-electro-Fenton process

J Environ Manage. 2022 Oct 1:319:115719. doi: 10.1016/j.jenvman.2022.115719. Epub 2022 Jul 15.

Authors

Ziyi Yang¹, Shimin Wu¹, Hangyu Sun¹, Samuel Gyebi Arhin¹, Vagelis G Papadakis², Maria A Goula³, Guangqing Liu⁴, Yi Zhang⁵, Ling Zhou⁶, Wen Wang⁷

Affiliations

¹ 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.
² Department of Environmental Engineering, University of Patras, Seferi 2, 30100, Agrinio, Greece.
³ Laboratory of Alternative Fuels and Environmental Catalysis, Department of Chemical Engineering, University of Western Macedonia, GR-50100, Greece.
⁴ Biomass Energy and Environmental Engineering Research Center, Beijing University of Chemical Technology, Beijing, 100029, China.
⁵ College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
⁶ Modern Agricultural Engineering Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region, Tarim University, Alar, Xinjiang Uygur Autonomous Region, 843300, China. Electronic address: zhoul-007@163.com.
⁷ 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. Electronic address: wangwen@mail.buct.edu.cn.

PMID: 35849928
DOI: 10.1016/j.jenvman.2022.115719

Abstract

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_app-6h) of about 0.12 h^-1. 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/cm² FCNT coated on the cathode electrode, 91.3% of the organic compounds were degraded, remaining only 84 mg/L COD (k_app-6h = 0.24 h^-1). 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 H₂O₂ production and the conversion between Fe²⁺ and Fe³⁺ by strengthening electrons generation and transportation via the oxidation of organics by biofilms (dominant with Geobacter) covered on the carbon brush.

Keywords: Bio-anode electrode; Bio-electro-fenton; Carbon black; Carbon nanotube; Landfill leachate.

MeSH terms

Biological Oxygen Demand Analysis
Electrodes
Hydrogen Peroxide / chemistry
Iron / chemistry
Organic Chemicals
Oxidation-Reduction
Water Pollutants, Chemical* / chemistry

Substances

Organic Chemicals
Water Pollutants, Chemical
Hydrogen Peroxide
Iron