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The aim of the presented study was to prepare the phosphate sorption isotherms of 20 European volcanic soil profiles and some other Hungarian and German volcanic soils (n = 114) used in the experiment and to establish the soil characteristics determining the phosphate sorption capacity of these soils. The Langmuir isotherm well describes the phosphate sorption of European volcanic soils at bright concentration interval 0–600 mg·dm -3 P. The calculated phosphate adsorption maximum (P max ) is an excellent soil property for characterizing the surface activity of soils developed on volcanic parent material. The calculated phosphate sorption maxima of soils included in the experiment ranged from 0 to 10.000 mg P·kg -1 . Some of the volcanic soils sorbed a high ratio of the added phosphate at low concentrations, while others sorbed somewhat less. The difference in the phosphate binding affinity of soils caused the differences in the shape of the Langmuir adsorption isotherms. P retention % is a WRB diagnostic requirement of andic soil horizon. It was supposed that the phosphate sorption maximum (P max ) gives a better characterization of the surface reactivity of volcanic soils. As it was predicted, oxalate soluble Al is the most important soil property, which dominantly (in 73%) explained the phosphate sorption ability of European volcanic soils.

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. The solid reactivity and toxicity of Cr is contingent upon oxidation state, with Cr(III) relatively immobile in the presence of solids and less toxic compared to Cr(VI), which remains in solution and is easily transported [ 14 ]. Sorption of Cr with

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In spite of good adsorption characteristics of activated carbon for molecular iodine, from water solution, problems arising due to complexity of chemistry of iodine and hydrolysis as well as influences of other relevant factors in water solutions which easily change the equilibrium concentrations toward domination of species with lower absorbability. Sorption of hypoiodus acid as predominant chemical form of iodine in neutral and weak alkaline solution within the range of micro concentrations has been studied in great details. In the experiments sorption of hypoiodous acid from water solutions on activated carbon with surface area of 1000 m2/g, under static and dynamic conditions, has been performed. Isotherms on various temperatures (25°C, 50°C, 70°C) has been obtained. Parameters of the sorption are determined and mechanism of adsorption of hypoiodous acid molecules on activated carbon has been discussed.

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The sorption behavior of technetium on pyrrhotine was studied with batch experiments and diluted sulfuric acid (less than 2.88 mol/l) was used to dissolve the technetium adsorbed on pyrrhotine. A significant sorption of technetium on pyrrhotine was observed under aerobic and anaerobic conditions, and the sorption on the mineral was supposed to be due to the reduction of TcO4 - to insoluble TcO2 .nH2O. Sorbed technetium on the mineral could be desorbed by diluted sulfuric acid. The maximum desorption ratio under aerobic conditions was much higher than that of under anaerobic conditions, meanwhile, the desorption rates under anaerobic conditions were higher than that of under aerobic conditions in the initial stage of the experiments.

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Inorganic sorbents are often used in separation of metals and radionuclides in radioanalytical application and they were also used in technological scale for separation of radionuclides in cleanup of Three Mile Island NPP. Inorganic sorbents become popular in the last years because no problem with organic contamination, there are stable against radiation, sorption efficiency can be tailor made for selective separation of chosen metal. Contrary to the organic sorbents they have usually lower capacity and chemical stability is limited to narrower pH. Nevertheless of some problems, many good properties of inorganic sorbents make them very attractive for sorption study.

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The sorption of45Ca on hair from a45CaCl2 solution /2.5×10–3 mol 1–1/ has been studied. The calcium amounts sorbed in 1 min to 5 h ranged between 0.8 and 7.2% with respect to the originally present calcium in hair.

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A fine-crystalline stannous ferrocyanide (SCF) has been prepared by adding tin(II) chloride to potassium hexacyanoferrate(II) solution. The material was characterized by chemical analysis, thermogravimetry, X-ray diffraction and infrared spectra. The solubility of SCF, kinetics and sorption mechanism of palladium in hydrochloric acid solutions were investigated. The palladium exchange capacity of 2.20 mM/g dry weight have been found.

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The sorption of cobalt on natural and modified clinoptiolites has been studied. It has been demonstrated that the higher sorption of cobalt on modified clinoptinolites than on natural ones is due to precipitation reactions. The precipitates formed on the sorbent have been investigated by infrared spectrometrical, microscopical, and X-ray analyses. The capacity values of the corresponding metal forms of clinoptilolite have been obtained with cobalt. Desactivation of radioactive solutions containing134Cs,137Cs204Tl and The sorption of cobalt on natural and modified clinoptiolites has been studied. It has been demonstrated that the higher sorption of cobalt on modified clinoptinolites than on natural ones is due to precipitation reactions. The precipitates formed on the sorbent have been investigated by infrared spectrometrical, microscopical, and X-ray analyses. The capacity values of the corresponding metal forms of clinoptilolite have been obtained with cobalt. Desactivation of radioactive solutions containing134Cs,137Cs,204Tl and60Co ions simultaneously on natural sorbents by precipitation reaction has been achieved.

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P.I. Gassman 2005 Impact of highly basic solutions on sorption of Cs + to subsurface sediments from the Hanford site, USA Geochimica et Cosmochimica Acta

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Selective sorption characteristics of electrolytic manganese dioxide (EMD) were investigated by dynamic tests using different types of water under varying conditions of235U activity, chemical species and flow rate in the presence of226Ra. EMD showed selectivity for ions having an effective ionic radius of about 1.4 Å indicating a selective sieve mechanism supporting a tunnel type structure. Sorption of235U under all experimental conditions is small (<1%) due to the larger sizes of urano-complexes (>3.54 Å). The Ra2+ ion (size 2.86 Å) was selectively extracted by EMD so that226Ra can be measured directly by gamma spectrometry using the 186 keV gamma line.

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