Sorption behavior

The sorption behavior of perfluorocarbon polymers is typical for nonpolar partially crystalline polymers (89). The weight gain strongly depends on the solubihty parameter. Litde sorption of substances such as hydrocarbons and polar compounds occurs. 

Porcelli D, Andersson PS, Baskaran M, Wasserburg GJ (2001) Transport of U- and Th-series in a Baltic Shield watershed and the Baltic Sea. Geochim Cosmochim Acta 65 2439-2459 Prikryl JD, Jain A, Turner DR, Pabalan RT (2001) Uraiunm (VI) sorption behavior on silicate mixtnres. J Cont Hydrol 47 241-253... 

A comprehensive survey is available in literature on the sorption behavior of elements over a range of hydrochloric acid concentrations. The compiled data show the following (i) a number of elements exhibit no sorption tendency at all (ii) many exhibit a change of behavior with hydrochloric acid concentration and (iii) several cases exhibit high distribution coefficients over at least some part of the concentration range. It can be found out that there is a possibility of separating certain metal combinations not easily obtainable by conventional chemical means. 

Three methods were used in this research to measure the extent of binding of organic pollutants to dissolved humic materials. They were equilibrium dialysis, solubility measurements and changes in sorption behavior in the presence of humic materials. Other authors have used solubility measurements, ultrafiltration and volatilization measurements. The methods will be described in the following paragraphs. 

The third technique we used was a measurement of changes in the sorption behavior of a compound in the presence of humic materials. A thin film of OV-1, a methyl silicone gum used as a chromatographic stationary phase, was plated on the bottom of a 60 ml Hypo-Vial (Pierce Chemical Co., Rockford, 11.). A solution of radiolabeled pollutant was added to the vial in either buffered distilled water in a solution of humic materials. Again, it is assumed that the pollutant is solution consists of two fraction free and bound. It is also assumed... 

The effect of physical aging on the crystallization state and water vapor sorption behavior of amorphous non-solvated trehalose was studied [91]. It was found that annealing the amorphous substance at temperatures below the glass transition temperature caused nucleation in the sample that served to decrease the onset temperature of crystallization upon subsequent heating. Physical aging caused a decrease in the rate and extent of water vapor adsorption at low relative humidities, but water sorption could serve to remove the effects of physical aging due to a volume expansion that took place in conjunction with the adsorption process. 

Borrok et al. (2004a) used potentiometric titration to measure Cd sorption by different bacterial consortia, and a surface complexation approach to determine thermodynamic stability constants. When the data were modeled by adopting a single set of stability constants, a similar sorption behavior was shown by a wide range of bacterial species. Further, current models that rely on pure strains of laboratory-cultivated bacterial species appear to overestimate the extent of metal biosorption in natural systems. 

Carrizosa MJ, Hermosin MC, Koskinen WC, Cornejo J (2004) Interactions of two sulfonylurea herbicides with organoclays. Clays Clay Miner 52 643-649 Celis R, Hermosin MC, Cornejo J (2000) Heavy metal adsorption by functionalized clays. Environ Sci Technol 34 4593-4599 Chappell MA, Laird DA, Thompson ML, Li H, Teppen BJ, Johnston CT, Boyd SA (2005) Influence of smectite hydration and swelling on atrazine sorption behavior. Environ. Sci Technol 39 3150-3156 Chiou CT (1989) Theoretical considerations of the partition uptake of nonionic organic compounds by soil organic matter. In Sawhney BL, Brown K (eds) Reactions and movement of organic chemicals in soils. Soil Science Society of America, Madison, WI, pp 1-29... 

The stoppers for vials contain a certain amount of water, which depends on the composition of the stoppers. De Grazio and Flynn [1.86] showed, that the selection of the polymer, the additives for the vulcanization, and the filler influence the adsorption and desorption of water. However even the best possible mixture increases the RM in 215 mg sucrose from 1.95 % to 2.65 % during 3 months storage time at room temperature. Other stopper mixtures show an increase up to 1.7 %. Pikal and Shah [1.87] demonstrated, that the desorption of water from the stopper and the absorption of water by the product depends, in the equilibrium state, on the mass and water content of the stopper and the water content and sorption behavior of the dry product. 

The description of the sorption process is largely based on empirical correlations, without knowledge of the detailed structure of the sediments. No doubt, in the future a greater effort will have to be made to understand sorption behavior in terms of sediment constituents. It will not suffice to consider sorption onto sediments simply in terms of partitioning into a uniform, thermodynamically ideal, stationary organic phase. 

The sorption behavior of 11 PAH compounds (a training set, Table 11) on various solid phases (e.g., three soils and two sediments) with different properties to relevant sorption (e.g., organic carbon content, clay content, pH, cation exchange capacity CEC Table 12), was determined by batch equilibrium studies [1]. Batch equilibrium tests were designed to determine rates of equilibrium sorption under conditions of high mixing and high surface areas of the solid particles (see Chap. 3). 

Lochmiiller, C.H. and Wilder, D.R., The sorption behavior of aUcyl bonded phases in reversed-phase, high performance liquid chromatography, J. Chromatogr. Sci., 17, 574, 1979. 

The migration/sorption behavior test for BHT and a-tocopherol in LDPE packaging materials in contact with fatty food simulants has indicated that the rate of migration of a-tocopherol into food simulants is lower than that for BHT. Since a-tocopherol was transferred from the film to the simulant to a lesser extent, it is considered a more stable antioxidant than BHT (Wessling et ah, 1998). BHT has also been found to migrate more rapidly than Irganox 1010 into dry food stored in LDPE wraps (Schwope et ah, 1987a). 

Nakamura, M., Suzuki, T., Amano, K., and Yamada, S. Relation of sorption behavior of agricultural chemicals in solid-phase extraction with their n-octanolAvater partition coefficients evaluated by high-performance liquid chromatography. Anal Chim. Acta, 428(2) 219-226, 2001. 

Singh, N. Sorption behavior of triazole fungicides in Indian soils and its correlation with soil properties. J. Agric. Food Chem., 50(22) 6434-6439, 2002. 

Turin, H.J. and Bowman, R.S. Sorption behavior and competition of bromacil, napropamide, and prometr3m, J. Environ. Qual., 26(5) 1282-1287, 1997. 

EXTRACT and O-METHYLATED EXTRACT. The sorption of benzene by the extract and the O-methylated extract is characterized by a rapid, initial uptake followed by a very slow approach to equilibrium. Such sorption behavior is very similar to that of glassy polymers. Thus we have chosen to interpret the sorption curves shown in Figures 2 and 3 in terms of the Berens-Hopfenberg model developed for the sorption of organic vapors into glassy polymers.(lS) By doing so, we attempt to correct the total sorption values for surface adsorption in order to calculate x parameters. 

R3D3 offers the results and interpretation for the water-sorption behavior of the medium-clay-content soil (S5). We include R3 below (slightly modified) ... 

The sorption of two weak acids (warfarin and thiopentone) and two weak bases (chlorpromazine and diltiazem) into PVC infusion bags was described by a constant partition model. PVC-water partition coefficients were obtained using three different methods equilibrium values for sorption into PVC bags, the sorption versus pH relationship, and partition into PVC strips. The data were compared with similar values derived from a liquid-liquid partition system and different organic solvents (octanol, dichloromethane, carbon tetrachloride, and hexane). Octanol is the preferred solvent, and it is suggested that octanol-water partition data can be used to predict sorption behavior [182]. 

Very recently, a major revision of the chemical pathways operating in the photocatalytic conversion of organic substrates was undertaken. Tliese studies were carried out through very careful product analysis [58,59], by using selected substrates with similar chemical properties but different sorption behavior [60], or by surface modification through complexation by redox inactive species [61,62]. 

Sorption Behavior of Tri valent Actinides and Rare Earths on Clay Minerals ... 

---