Long-term anaerobic conversion of lindane by electrochemically generated hydrogen
Lindane (γ‑HCH) persists in many aquifers where electron‑donor scarcity limits reductive dechlorination. Here we present a long‑term (116 d) microbial electrochemical technology (MET) that supplies cathodic H₂ to sustain lindane biotransformation. Sequentially decreasing the graphite‑brush cathode p...
| Autores: | , , , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2026 |
| País: | España |
| Recursos: | Universitat Autònoma de Barcelona |
| Repositório: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglês |
| OAI Identifier: | oai:dnet:uabarcelona_::06b46137fd08dabac6fd7477e733fc28 |
| Acesso em linha: | https://ddd.uab.cat/record/328872 https://dx.doi.org/urn:doi:10.1016/j.jhazmat.2026.142242 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Lindane Microbial electrochemical technology Reductive dechlorination Hydrogen Microbial community Shewanella Pseudomonas |
| Resumo: | Lindane (γ‑HCH) persists in many aquifers where electron‑donor scarcity limits reductive dechlorination. Here we present a long‑term (116 d) microbial electrochemical technology (MET) that supplies cathodic H₂ to sustain lindane biotransformation. Sequentially decreasing the graphite‑brush cathode potential from −0.6 to −0.7 and −0.8 V versus SHE raised headspace H₂ from < 0.1% to > 1% (v/v) and accelerated lindane degradation rates. Product inhibition led by the accumulation of monochlorobenzene and benzene stalled the culture. The application of three 15‑min N₂ flushing cycles restored activity each time and boosted the removal rate from 33.3 ± 1.2 (µM/d) to 85.3 ± 4.5 (µM/d) at −0.8 V. The value of the poised cathodic potential also affected the product distribution ratio of monochlorobenzene to benzene. Thus, the MET did not just provide a source of electrons but also seems to have an impact on the transformation pathway of lindane. 16S‑rRNA profiling revealed a biocathode dominated by Shewanella (14.6 ± 5.8%) and Pseudomonas (35.0 ± 8.2%), two genera potentially involved either in the direct transformation of lindane or in establishing an interspecies electron transfer network that enhances its reduction. |
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