Sorbents, solid, evaluation

We evaluated removal performance by contacting a weighed amount of the sorbent with a measured volume of solution in a shaker bath at 25 2 °C. For titanium-containing sorbents, we add the sorbent to provide the equivalent amount of titanium as that from 0.4 g/L MST. For non-titanium materials, we added the sorbent to provide the same number of equivalents as that provided by 0.4 g/L MST. Typically, we sampled the batch-contact test bottles after 4, 24 and 168 hours and measured solution phase strontium and actinide concentrations after removing sorbent solids by filtration. 

Enthalpy of adsorption it represents another critical parameter in the evaluation of the performance of solid sorbents. It is a measure of the energy required to regenerate the solid sorbent, and it therefore significantly influences the cost of the regeneration process. It represents the affinity of the material toward C02 and measures the strength of the adsorbate-adsorbent interaction. 

Pierce, R., et al.. Evaluation of solid sorbents for the recovery of polyether toxins (brevetoxins) in seawater. Bull. Env. Contam. Toxicol., 49, 479, 1992. 

Weber, W.J., Jr., Voice, T.C., Pirbazari, M., Hunt, G.E., and Ulanoff, D.M. Sorption of hydrophobic compounds by sediments, soils, and suspended solids. 11. Sorbent evaluation studies, WaterRes., 17(10) 1443-1452, 1983. 

Andersson K, Levin JO, Nilsson CA. 1983. Evaluation of solid sorbents for sampling aliphatic and aromatic nitro compounds. Chemosphere 12 377-384. 

This overall study of acid mists began with the development of a sampling and analytical method for hydrogen chloride ((>,7). Various solid sorbents and filters, both treated and untreated, were evaluated as collection media and for compatibility with ion chromatography. The sorbent of choice was silica gel which had been washed with deionized water to remove inorganic impurities. 

Melcher, R. G. Langner, R. R. Kagel, R. 0. Criteria for the Evaluation of Methods for the Collection of Organic Pollutants in Air Using Solid Sorbents,... 

The examples presented in this paper are based on results of our laboratory method development and validation studies. These studies, performed at both SRI International and Arthur D. Little, Inc., were supported by the National Institute for Occupational Safety and Health (NIOSH) from 1974 to 1979. In an effort to provide validated sampling and analytical methods for determining worker exposure to toxic substances, we validated existing methods when possible and developed and validated new procedures when no methods were available. Evaluation and testing of solid sorbents played a major role throughout this work ( 1). 

Harris, J. C. Cohen, M. J. Grosser, Z. A. Hayes, M. J. Evaluation of Solid Sorbent for Water Sampling Arthur D. Little, Inc. U.S. Environmental Protection Agency. U.S. Government Printing Office Washington, DC, 1980 EPA Report No. 600/2-80-193. 

Subramanian and coworkers developed polymeric sorbents using different support materials (such as Merrifield chloromethylated resin, Amberlite XAD 16) and complexing ligands (amides, phosphonic acids, TTA), and evaluated their binding affinity for U(VI) over other diverse ions, even under high acidities. The practical utility of these sorbents was demonstrated using simulated waste solutions (220-222). Shamsipur et al. reported the solid-phase extraction of ultra trace U(VI) in natural waters using octadecyl silica membrane disks modified by TOPO (223). The method was found satisfactory for the extraction and determination of uranium from different water samples. 

Anthemidis, A.N. and K.-I.G. Ioannou. 2006. Evaluation of polychlorotrifluoroethylene as sorbent material for on-line solid phase extraction systems Determination of copper and lead by flame atomic absorption spectrometry in water samples. Anal. Chim. Acta 575 126-132. 

Laskin-Type Nozzle Generator. A third type of atomizer, the Laskin-type nozzle generator, is used to create test atmospheres of particulate or aerosol and vapor mixtures. A pure liquid or melt is used, and no solvent is necessary. Again, this is important for evaluating filter and solid sorbent combination sampling trains. 

Presented are the examinations of the multifimctional mineral-earbon and zeolite-carbon sorbents prepared from kaolinite with an admixture of carbonaceous materials industrial waste deposits, municipal sewage sludge and cellulose. The mixture of raw materials was thermally and hydrothermally pretreated in order to facilitate their specific structure. The parameters of capillary structure (micro and mesopores) were determined. For examinations of porous structure the mereury porosimetry method was used. In order to evaluate the solid phase transformation during the each step of sorbent preparation the SEM observation with quantitative X-ray mieroanalysis were made. 

In evaluating the mechanistic models for sorption by coals, one is well advised to consider the contrast of the two general classes of sorbents physical adsorption (sometimes called physisorption) will likely alter the surface structure of a molecular solid adsorbent (such as ice, paraffin, and polymers), but not that of high surface energy, refractory solids (such as the usual metals and metal oxides, and carbon black) (9). Adamson (27) has proposed... 

Solid-phase extraction (SPE) is an alternative to LLE. In SPE the analytes are partioned between a solid and a liquid [57, 58], Generally, interfering compounds are rinsed off the solid adsorbent and the analytes are then desorbed with an eluting solvent [58], A range (e.g., normal-phase, reversed-phase, ion exchange, restricted access) of sorbents and formats are available for SPE and the SPE systems are easy to automate [59, 60], In order to accomplish the isolation of the products from the fermentation matrix, both SPE and LLE were evaluated for use in papers I and II. 

Dzygiel, P. O Donnell, E. Fraier, D. Chassaing, C. Cormack, P. A. G., Evaluation of water-compatible molecularly imprinted polymers as solid-phase extraction sorbents for the selective extraction of sildenafil and its desmethyl metabolite from biological samples, J. Chromatogr. B 2007, 853(1-2), 346-353... 

Equation 6 can be shown to correspond in mathematical form to a model predicated on a continuous spectrum of sorption interaction energies. If this interpretation is imposed on equation 6, the variable n can be said to reflect both the level and distribution of sorption energies, and KF the sorption capacity. For most natural solids, n generally ranges in value between 0.5 and 1.0, the upper limit characterizing a linear isotherm. As defined, KF would logically incorporate the specific reactive surface area, SH, of the sorbent, which can be abstracted to yield a capacity term, KFh, expressed per unit surface area (KFh = KF/SH). A logarithmic transform of equation 6 can be used to facilitate evaluation of both KVu and n from observed equilibrium sorption data. 

Guenu, S. and Hennion, M. C. 1996. Evaluation of new polymeric sorbents with high specific surface-areas using an online solid-phase extraction liquid-chromatographic system for the trace-level determination of polar pesticides, J. Chromatog., 737 15-24. 

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