Soil sorption from water

Soil sorption partition coefficient (or soil-water partition coefficient), denoted as Kqc or logKoc accounts for sorption from water into soil. Because this often depends primarily on the soil s organic carbon content, measured values are usually normalized for the organic carbon (OC) content of soil, in which case the soil sorption equilibrium constant is expressed as... 

Vapor pressure (VP), water solubility ( w), and soil sorption coefficients Koc) are key properties that govern volatilization of agrochemicals from soil. Volatile compounds such as 5 -ethyl dipropylthiocarbamate (EPTC) (VP 4.5 Pa,... 

Pigna M, Colombo C, Violante A (2003) Competitive sorption of arsenate and phosphate on synthetic hematites (in Italian). Proceedings XXI Congress of Societa Italiana Chimica Agraria SICA (Ancona), pp 70-76 Quirk JP (1955) Significance of surface area calculated from water vapour sorption isotherms by use of the B. E. T. equation. Soil Sci 80 423-430 Rancourt DG, Fortin D, Pichler T, Lamarche G (2001) Mineralogical characterization of a natural As-rich hydrous ferric oxide coprecipitate formed by mining hydrothermal fluids and seawater. Am Mineral 86 834-851 Raven K, Jain A, Loeppert, RH (1998) Arsenite and arsenate adsorption on ferrihydrite kinetics, equilibrium, and adsorption envelopes. Environ Sci Technol 32 344-349... 

Pollutants with high VP tend to concentrate more in the vapor phase as compared to soil or water. Therefore, VP is a key physicochemical property essential for the assessment of chemical distribution in the environment. This property is also used in the design of various chemical engineering processes [49]. Additionally, VP can be used for the estimation of other important physicochemical properties. For example, one can calculate Henry s law constant, soil sorption coefficient, and partition coefficient from VP and aqueous solubility. We were therefore interested to model this important physicochemical property using quantitative structure-property relationships (QSPRs) based on calculated molecular descriptors [27]. 

Adsorption to particulate matter will transport disulfoton from water to suspended solids and sediment in water. The estimated organic carbon-adjusted soil sorption coefficient (K°<=) for disulfoton varies between 600 and 1,603 (Jury et al. 1987a Rao and Davidson 1982 Wauchope et al. 1992). This, range of K°= values suggests that disulfoton in water absorbs moderately to suspended solids and sediments (Swann et al. 1983), and this process may transport considerable amounts of disulfoton from water to particulate matter. 

As a result of its persistence in soil and groundwater, and past widespread use as a gasoline additive and fumigant, 1,2-dibromoethane has been detected in ambient air, soils, groundwater, and food. However, most of the monitoring data reported in this section, although the latest available, are not current. Volatilization is the most important removal process for 1,2-dibromoethane released to surface waters. Since only a small fraction of the compound is sorbed to soil, sorption to sediment and subsequent persistence in sediment is not expected to be an important process in the removal of 1,2-dibromoethane from the environment. The data may reflect ambient concentrations of a decade or more ago, but because of the phaseout of the use of leaded gasoline and the ban on... 

Walsh, P.R. and Hites, R.A.Dicofol solubility and hydrolysis in water. Bull. Environ. Contam. Toxicol, 22(3) 305-311,1979. Walters, R.W. and Guiseppi-Elie, A. Sorption of 2,3,7,8-tetrachlorodibenzo-/t-dioxin to soils from water/methanol mixtures. 

Steroid hormones form a group of pollutants that includes natural hormones such as estradiol, testosterone, and their metabolites as well as several synthetic analogues. Steroid hormones used as growth promoters have already been found in water and sediments (Lai et al. 2000 Thorpe et al. 2003), and their adsorption properties on earth materials have been considered. Lee et al. (2003) report batch experiments where simultaneous sorption of three hormones (17- 3-estradiol, 17-a-ethyl estradiol, and testosterone) on four midwestem U.S. soils and a freshwater sediment were performed. Apparent sorption equilibria were reached within a few hours. Sorption isotherms generally were linear for the chemicals studied on one of these soils (Drummer soil), ranged from 23.4 to 83.2 L kg and log ranged... 

In this first example, extraction of the contaminant from water is of par ticular interest for a number of reasons, not the least of which is that extraction requires no particular pretreatment of the contaminated fluid. Air can be injected into the soil around the aquifer and recovered in sorption towers for concentration and removal from the environment. Alternatively, the water can be pumped from the aquifer < ) 2005 by CRC Press LLC... 

Chiou, C. T., D. E. Kile, D. W. Rutherford, G. Shung, and S. A. Boyd, Sorption of selected organic compounds from water to a peat soil and its humic-acid and humin fractions Potential sources of the sorption nonlinearity , Environ. Sci. Technol., 34,1254-1258 (2000). 

Poole, S. K., and C. F. Poole, Chromatographic models for sorption of neutral organic compounds by soil from water and air , J. Chromatogr. A, 845, 381-400 (1999). 

The fate of surfactants in soils and surface waters is determined primarily by biodegradation and sorption. Biodegradability depends on the presence of functional groups in surfactants which can be metabolized by microorganisms. Surfactant sorption depends on a) the ability of a surfactant headgroup to undergo interactions with the sorbent and b) the interactions of its hydrophobic tail which is repelled from the water. 

Time Beach soilAvater with 0.01% surfactant from Missouri at pH 4, 7, 8.5, Puri et al. 1989) 5.70, 5.09, 4.76 (Visalia soilAvater with 0.01% surfactant from California at pH 4, 7, 8.5, Puri et al. 1989) 6.44, 6.66 (batch equilibrium-sorption isotherms 2-d, 10-d isotherm, regression analysis for sorption of uncontaminated Time Beach soil from water, Walters et al. 1989)... 

Walters, R.W., Ostazeski, S.A., Guiseppi-Elie, A. (1989) Sorption of 2,3,7,8-tetiachlorodibenzo-p-dioxin from water by surface soils. Environ. Sci. Technol. 23(4), 480 184. 

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