The Fe-doped biochar cathode-modified electro-Fenton formed through one-pot pyrolysis of two solid wastes holds the potential to degrade emerging contaminants in actual wastewater: Singlet oxygen plays a dominant role

Heterogeneous electro-Fenton (HEF) technology is considered an effective method for degrading emerging contaminants in wastewater, and the recycling of solid waste is deemed a more environmentally friendly means of manufacturing cathode materials. In this study, a series of modified biochar (Jarx) featuring an obvious porous structure, active defects, and abundant oxygen-containing functional groups were synthesized through the pyrolysis of industrial solid waste jarosite and distillers’ grains using a simple one-pot method. Within 5 h, the HEF system demonstrated a highly efficient elimination rate of dimethyl phthalate (DMP) of 82.64 % and TOC removal of 51.46 % under neutral conditions, along with low Fe leaching of 0.039 mg/L. It was demonstrated that singlet oxygen plays a crucial part in the process. The catalyst (AMDS-1), which was synthesized by employing acid mine drainage sludge as a substitute for jarosite, also sustained comparable degradation performance for DMP. Additionally, the system exhibits excellent recyclability, anti-interference ability and practicability, and is capable of effectively degrading atrazine, chloramphenicol, quinoline and bisphenol A. Moreover, it can even eliminate 8.66 % of dibutyl phthalate and 72.44 % of perfluorooctanoic acid in the actual landfill leachate. This study offers valuable experience for the synthesis of green and economical HEF cathode materials to effectively degrade emerging contaminants in the actual aquatic environment through the approach of “treating waste with waste”. Copyright © 2025 Elsevier B.V.