Citation:

Walters, R. W. AND A. GuiseppiElie. SORPTION OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN TO SOILS FROM WATER/METHANOL MIXTURES. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, 22(7):819-825, (1988).

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Sorption of ¹⁴C-labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to soils from water/methanol mixtures has been evaluated by batch shake testing. Uncontaminated soils from Times Beach, MO, were used in these experiments and ranged in fraction organic carbon (U+0192_oc from 0.0066 to 0.077. Volume fraction methanol in the liquid phase (U+0192_sa; at U+0192_s of 0.5, sorption equilibrium for low-U+0192_oc soils was achieved within 1 day, while sorption to the high-U+0192_oc soil required as long as 30 days to reach equilibrium. For U+0192_s of 1.0 and the high-U+0192_oc soil, sorption equilibrium was attained in about 10 days. Sorption isotherms were linear, and when sorption partition coefficients (K_D, mL/g) were converted to K_m (mol/g), these latter values were log-linearly related to fa. K, values for two soils, when normalized on U+0192_oc, gave values of K_m,_oc that collapsed onto a single line having the equation determined by linear regression analysis: log K_m,_oc = -4.97U+0192_s + 5.30 with r₂ = 0.98 and s = 0.20. log K_oc, the logarithm of the aqueous-phase partition coefficient normalized on f_oc, for TCDD extrapolated from this relationship is 6.6 ± 0.7. The slope of the log-linear relationship is related to the effect off, on TCDD solubility and on TCDD-soil and solvent-soil interactions. Data presented here suggest that the latter solvent-soil interactions may not increase TCDD accessibility to soil organic matter to the same extent as that reported for less hydrophobic organic solutes.

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SORPTION OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN TO SOILS FROM WATER/METHANOL MIXTURES  

Record Details:

Record Type:DOCUMENT( JOURNAL/ PEER REVIEWED JOURNAL)

Product Published Date:07/01/1988

Record Last Revised:02/06/2009

OMB Category:Other

Record ID: 129215

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Access Procedures :Public

Document IDs:

EPA Number :EPA/600/J-88/321

NTIS Number : 89-207344