Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-10T05:31:16.620Z Has data issue: false hasContentIssue false

Hydrophobicity of Clay Surfaces: Sorption of 1,2-Dibromoethane and Trichloroethene

Published online by Cambridge University Press:  02 April 2024

B. L. Sawhney
Affiliation:
The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504
M. P. N. Gent
Affiliation:
The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Sorption and desorption of two neutral, nonpolar organic compounds, 1,2-dibromoethane (EDB, a soil fumigant) and trichloroethene (TCE, an industrial solvent and common ground-water contaminant), by pyrophyllite, kaolinite, illite, and smectite were investigated. For sorption, vapors of the compounds in a stream of dry N2 gas were passed through columns of the powdered clay minerals for different periods of time. The compounds retained by the clays were extracted with methanol and analyzed by gas chromatography (GC). For desorption, N2 was passed through the treated samples, and the desorbed compounds were collected in hexane traps and analyzed by GC.

Initially sorption was rapid for several hours but then proceeded at a slower rate for many hours. Surprisingly, the clays sorbed large quantities of these neutral compounds; for example, the pyrophyllite, kaolinite, illite, and smectite sorbed about 3, 5, 6, and 9% EDB, respectively, by weight. The amounts of TCE sorbed, which is more volatile than EDB, were somewhat less. Only a portion of the compounds sorbed over a period of time were desorbed in the same period of time. Desorption was rapid initially but then proceeded at a slow rate; slow desorption continued for over 100 hr from samples which had undergone sorption for only 1–2 hr. A two-compartment efflux model was used to describe the sorption behavior. A rapidly desorbing component was considered to be present on the outer surfaces of the clay aggregates and a slowly desorbing component, in the interior pores of the aggregates.

Type
Research Article
Copyright
Copyright © 1990, The Clay Minerals Society

References

Chiou, C. T., 1989 Theoretical considerations of the partition uptake of non-ionic organic compounds by soil organic matter Reactions and Movement of Organic Chemicals in Soils 22 129.Google Scholar
Chiou, C. T., Porter, P. E. and Schmedding, D. W., 1983 Partition equilibria of nonionic organic compounds between soil organic matter and water Environ. Sci. Technol. 17 227231.CrossRefGoogle Scholar
Chiou, C. T. and Shoup, T. D., 1985 Soil sorption of organic vapors and effects of humidity on sorptive mechanism and capacity Environ. Sci. Technol. 19 11961200.CrossRefGoogle ScholarPubMed
Estes, T. J., Shah, R. V. and Vilker, V. L., 1988 Adsorption of low molecular weight halocarbons by montmorillonite Environ. Sci. Technol. 22 377381.CrossRefGoogle Scholar
Garbarini, D. R. and Lion, L. W., 1986 Influence of the nature of soil organics on the sorption of toluene and trichloroethylene Environ. Sci. Technol. 20 12631269.CrossRefGoogle Scholar
Greenland, D. J. and Hayes, M. H. B., 1978 The Chemistry of Soil Constituents New York Wiley.Google Scholar
Gregg, S. J., 1951 The Surface Chemistry of Solids New York Reinhold.Google Scholar
lier, R. K., 1979 The Chemistry of Silica New York Wiley.Google Scholar
Jurinak, J. J., 1957 The effect of clay minerals and exchangeable cations on the adsorption of ethylene dibromide vapor Soil Sci. Soc. Amer. Proc. 21 599602.CrossRefGoogle Scholar
Karickhoff, S. W., 1984 Organic pollutant sorption in aquatic systems J. Hydraul. Div. Amer. Soc. Civil Eng. 110 707735.CrossRefGoogle Scholar
Karickhoff, S. W., Brown, D. S. and Scott, T. A., 1979 Sorption of hydrophobic pollutants on natural sediments Water Res. 13 241248.CrossRefGoogle Scholar
Karickhoff, S. W. and Morris, K. R., 1985 Impact of turbificid oligochaetes on pollutant transport in bottom sediments Environ. Sci. Technol. 19 5156.CrossRefGoogle Scholar
Karickhoff, S. W. and Morris, K. R., 1985 Sorption dynamics of hydrophobic pollutants in sediment suspensions Environ. Toxicol. Chem. 4 469479.CrossRefGoogle Scholar
MacIntyre, W. G. and Smith, C. L., 1984 Comment on “Partition equilibria of nonionic organic compounds between soil organic matter and water” Environ. Sci. Technol. 18 295.CrossRefGoogle Scholar
McCall, P. J. and Agin, G. L., 1985 Desorption kinetics of picloram as affected by residence time in the soil Environ. Toxicol. Chem. 4 3744.CrossRefGoogle Scholar
Mingelgrin, U. and Gerstl, Z., 1983 Réévaluation of partitioning as a mechanism of nonionic chemicals adsorption in soils J. Environ. Qual. 12 111.CrossRefGoogle Scholar
Mortland, M. M., 1986 Mechanisms of adsorption of nonhumic organic species by clays Interactions of Soil Minerals with Natural Organics and Microbes 17 5976.Google Scholar
Pignatello, J. J., 1989 Sorption dynamics of organic compounds in soils and sediments Reactions and Movement of Organic Chemicals in Soils 22 4580.Google Scholar
Pinnavaia, T. J., 1983 Intercalated clay catalysts Science 220 365371.CrossRefGoogle ScholarPubMed
Raussell-Colom, J. A., Serratosa, J. M. and Newman, A. C. D., 1987 Reactions of clays with organic substances Chemistry of Clays and Clay Minerals New York Wiley 371422.Google Scholar
Sawhney, B. L., 1985 Vapor-phase sorption and polymerization of phenols by smectite in air and nitrogen Clays & Clay Minerals 33 123127.CrossRefGoogle Scholar
Sawhney, B. L. and Brown, K. (eds.) (1989) Reactions and Movement of Organic Chemicals in Soils: Soil Sci. Soc. Amer. Special Publ. 22, 474 pp.Google Scholar
Sawhney, B. L., Pignatello, J. J. and Steinberg, S. M., 1988 Determination of 1,2-dibromoethane (EDB) in field soils: Implications for volatile organic compounds J. Environ. Qual. 17 149152.CrossRefGoogle Scholar
Steinberg, S. M., Pignatello, J. J. and Sawhney, B. L., 1987 Persistence of 1,2-dibromoethane in soils: Entrapment in intraparticle micropores Environ. Sci. Technol. 21 12011208.CrossRefGoogle Scholar
Weber, W. J. Jr. Voice, T. C., Pirbazari, M., Hunt, G. E. and Ulanoff, D. M., 1983 Sorption of hydrophobic compounds by sediments, soils and suspended solids—II Water Res. 17 14431452.CrossRefGoogle Scholar
Wu, S. and Gschwend, P. M., 1986 Sorption kinetics of hydrophobic organic compounds to natural sediments and soils Environ. Sci. Technol. 20 717725.CrossRefGoogle ScholarPubMed