Application of a membrane model to the sorptive interactions of humic substances
- Geological Survey, Arvada, CO (USA)
Humic substances, the dark-colored, natural organic polyelectrolytes that are found in practically all soils, sediments, and natural water, strongly interact with both inorganic and organic pollutants. Inorganic cationic species generally undergo complexation reactions with humic substances. The binding of cations, such as cupric ions, by humic substances often markedly reduces their toxicity to aquatic organisms. Some inorganic anionic species, in the presence of metal ions, are sorbed by humic substances. In these instances the metal ions appear to form bridges between the humic substances and the anions. Several different types of interactions take place between organic compounds and humic materials. Hydrophobic organic species partition into either insoluble or soluble humic substances. The insoluble humic substances will remove hydrophobic organic compounds from the aqueous phase, thereby rendering them less mobile. However, soluble humic substances will solubilize hydrophobic organics, increasing their mobility. These various interactions between humic substances and pollutants are important in governing their fate and movement in natural water systems, and, for this reason, a detailed understanding of the mechanisms of the interaction is important. A recently developed membrane model of the structure of humic substances is described.
- OSTI ID:
- 7064673
- Journal Information:
- Environmental Health Perspectives; (USA), Journal Name: Environmental Health Perspectives; (USA) Vol. 83; ISSN 0091-6765; ISSN EVHPA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
540320* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (1990-)
ANIONS
CATIONS
CHARGED PARTICLES
CHEMISTRY
FULVIC ACIDS
GEOLOGY
GROUND WATER
HUMIC ACIDS
HUMUS
HYDROGEN COMPOUNDS
HYDROLOGY
IONS
MATHEMATICAL MODELS
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
POLLUTION
SOIL CHEMISTRY
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
WATER
WATER POLLUTION