Influence of organic cosolvents on sorption of hydrophobic organic chemicals by soils

Journal Article · Tue Oct 01 00:00:00 EDT 1985 · Environ. Sci. Technol.; (United States)

DOI:https://doi.org/10.1021/es00140a015· OSTI ID:5532837

Nkedi-Kizza, P; Rao, P S.C.; Hornsby, A G

Sorption of anthracene and two herbicides (diuron and atrazine) by soils from aqueous solutions and binary solvent mixtures consisting of methanol-water and acetone-water was measured. These data were used to evaluate recently proposed solvophobic theory for describing sorption of hydrophobic molecules from mixed solvents. As predicted by the theory, the sorption coefficient (K/sup m/) decreased exponentially with increasing fraction of the organic cosolvent (f/sup c/) in the binary solvent mixtures. The slope of the ln K/sup m/ vs. f/sup c/ plot, designated as sigma/sup c/, was unique to each sorbate-solvent combination and was independent of the soil (sorbent). Thus, the organic cosolvent effects on sorption could be specified by a single parameter that combines the coefficients characterizing solvent and sorbate properties. The sigma/sup c/ value was shown to be directly proportional to the solvent-sorbate interfacial free energy( ..delta gamma../sup c/) and the hydrocarbonaceous molecular surface area (HSA) of the sorbate.

• Research Organization: Univ. of Florida, Gainesville
• OSTI ID: 5532837
• Journal Information: Environ. Sci. Technol.; (United States), Vol. 19:10
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ANTHRACENE
AQUEOUS SOLUTIONS
SORPTION
HERBICIDES
SOILS
CHEMICAL PROPERTIES
PHYSICAL PROPERTIES
ORGANIC SOLVENTS
AROMATICS
CONDENSED AROMATICS
DISPERSIONS
HYDROCARBONS
MIXTURES
ORGANIC COMPOUNDS
PESTICIDES
SOLUTIONS
SOLVENTS
510200* - Environment
Terrestrial- Chemicals Monitoring & Transport- (-1989)