Plant-substrate biochar properties critical for mediating reductive debromination of 1,2-dibromoethane

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt


  • Fulltext

    Forlagets udgivne version, 1,33 MB, PDF-dokument

Dibromoethane is a widespread, persistent organic pollutant. Biochars are known mediators of reductive dehalogenation by layered FeII-FeIII hydroxides (green rust), which can reduce 1,2-dibromoethane to innocuous bromide and ethylene. However, the critical characteristics that determine mediator functionality are lesser known. Fifteen biochar substrates were pyrolyzed at 600 °C and 800 °C, characterized by elemental analysis, X-ray photo spectrometry C and N surface speciation, X-ray powder diffraction, specific surface area analysis, and tested for mediation of reductive debromination of 1,2-dibromoethane by a green rust reductant under anoxic conditions. A statistical analysis was performed to determine the biochar properties, critical for debromination kinetics and total debromination extent. It was shown that selected plant based biochars can mediate debromination of 1,2-dibromoethane, that the highest first order rate constant was 0.082/hr, and the highest debromination extent was 27% in reactivity experiments with 0.1 µmol (20 µmol/L) 1,2-dibromoethane, ≈ 22 mmol/L FeIIGR, and 0.12 g/L soybean meal biochar (7 days). Contents of Ni, Zn, N, and P, and the relative contribution of quinone surface functional groups were significantly (p < 0.05) positively correlated with 1,2-dibromoethane debromination, while adsorption, specific surface area, and the relative contribution of pyridinic N oxide surface groups were significantly negatively correlated with debromination.

TidsskriftJournal of Environmental Sciences
Antal sider10
StatusUdgivet - 2025

Bibliografisk note

Funding Information:
The authors thank the Sino Danish Center for financial support. We also extent our gratitude to Anita Sandager, Birgitte Rasmussen, and the rest of the technical staff at the section for Environmental Chemistry and Physics, University of Copenhagen for support and lab assistance. Furthermore, we thank the donors of plant substrates: Helle & Wagner Hessner at Duelund farm, Nordic Sugar A/S, K&S Treecare, and Møn Tang.

Publisher Copyright:
© 2023

ID: 382753037