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Updated: Jan 26, 2026

Quantification of Humic and Fulvic Acids in Humate Ores, DOC, Humified Materials and Humic Substance-Containing Commercial Products
Published on: March 18, 2022
Polarity and Molecular Weight of Compost-Derived Humic Acids Impact Bio-dechlorination of Pentachlorophenol
Ying Yuan1,2, Beidou Xi1, Xiao-Song He1
1State Key Laboratory of Environmental Criteria and Risk Assessment , Chinese Research Academy of Environmental Sciences , Beijing 100012 , China.
Abstract:
Compost-derived humic acids (HAs) as cheap soil conditioners have potential to facilitate pentachlorophenol (PCP) bio-dechlorination but lack proof and studies. To clarify this, PCP bio-dechlorination mediated by compost-derived HAs under Fe(III) reduction conditions was investigated. Reverse phase high-performance liquid chromatography and high-performance size exclusion chromatography were employed to identify the functional components within compost-derived HAs. Our results showed that compost-derived HAs facilitated the bio-dechlorination of PCP under Fe(III) reduction conditions, and four kinds of byproducts were detected during the process. The relatively hydrophilic and high molecular weight (MW) components within compost-derived HAs presented significant associations with the concentration of byproducts from bio-dechlorination of PCP in Fe2O3 reduction conditions. In contrast, the hydrophobic and low MW components were the main functional components for PCP bio-dechlorination in Fe3O4 reduction environment. These findings clarified the effects of polarity and MW of compost-derived HAs on PCP bio-dechlorination, giving clues to optimize composting technology to utilize compost products for in situ contamination remediation of paddy soil.
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