Copper-binding ability of dissolved organic matter derived from anaerobically digested biosolids

Journal Article · Sat May 01 04:00:00 EDT 1999 · Journal of Environmental Quality

DOI:https://doi.org/10.2134/jeq1999.00472425002800030026x· OSTI ID:364035

Han, N; Thompson, M L ^[1]

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1. Iowa State Univ., Ames, IA (United States). Agronomy Dept.

The fate of metals in soils where soluble organic compound are present may be strongly influenced by the degree to which they are complexed by organic ligands. The authors undertook this study to determine the combined effect of molecular weight (MW) and hydrophobicity on the Cu-binding ability of dissolved organic compounds in biosolids (i.e., sewage sludge). Dissolved organic matter (DOM) from anaerobically digested sewage biosolids was fractionated by using a combination of MW fractionation and XAD-8 resin chromatography. The Cu-binding abilities of the DOM fractions were obtained by using a Cu{sup 2+}-ion-selective electrode (Cu-ISE) technique. The Cu-binding ability of fractionated DOM decreased significantly with increasing molecular weight, indicating that low-MW DOM had more metal-binding sites than high-MW DOM. Within each MW fraction, the hydrophilic and the hydrophobic components also exhibited differences in Cu-binding ability. For the DOM with MW 500--3,500 Da, the hydrophilic fraction showed a greater Cu-binding capacity than did the hydrophobic fraction, whereas the hydrophobic acid components were most important in binding Cu for DOM with MW > 3,500 Da. The maximum Cu-binding capacities of different biosolids-derived DOM fractions, estimated by employing a Langmuir model, ranged from 1.85 to 14.3 mmol Cu mol{sup {minus}1} dissolved organic C (DOC), which is the same order of magnitude as similar measurements of DOM from other sources.

• Sponsoring Organization: USDOE
• OSTI ID: 364035
• Journal Information: Journal of Environmental Quality, Journal Name: Journal of Environmental Quality Journal Issue: 3 Vol. 28; ISSN JEVQAA; ISSN 0047-2425
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
COPPER
ENVIRONMENTAL TRANSPORT
GROUND WATER
MATHEMATICAL MODELS
ORGANIC MATTER
SEWAGE SLUDGE
SOIL CHEMISTRY
SOILS