Abstract
In this study, we explored the correlation between the catalytic activity of UK Biochar Research Center biochars (BCs) and their physicochemical properties, suggesting a potential role of endogenous iron in promoting their persulfate activation capability by heat treatment. A steady improvement in the persulfate activation efficiency with increasing annealing temperature was observed exclusively for iron-containing BCs (e.g., sewage sludge (SS) BCs). Along with increasing the Brunauer–Emmett–Teller surface area, thermal annealing formed carbon-wrapped iron particles on the SS BC surfaces, produced crystalline elemental iron and iron carbides, and caused an sp3-to-sp2 conversion in the carbon phase. Comparing the annealed SS BCs in terms of the open circuit potential shift, electrical conductivity, and thermodynamic binding parameters showed that the heat-initiated modification enhanced the electron transfer-mediating capacity and surface affinity toward persulfate, which led to the beneficial effect of annealing on the carbocatalytic activity of iron-containing BCs for non-radical persulfate activation.
Original language | English |
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Article number | 122647 |
Journal | Applied Catalysis B: Environmental |
Volume | 330 |
DOIs | |
Publication status | Published - 2023 Aug 5 |
Bibliographical note
Funding Information:This study was supported by a National Research Foundation of Korea grant funded by the Korean government (grant no. 2021R1A2C2003763 ) and the Korea Ministry of Environment (grant no. RE202201829 ) and Korea Environment Industry and Technology Institute ( KEITI ) through the Developing Innovative Drinking Water and Wastewater Technologies Project ( 2022002710001 ).
Publisher Copyright:
© 2023 Elsevier B.V.
Keywords
- Biochar
- Carbon-encapsulated iron
- Non-radical oxidation
- Persulfate activation
- Thermal annealing
ASJC Scopus subject areas
- Catalysis
- General Environmental Science
- Process Chemistry and Technology