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dc.contributor.advisorErten, Hasan N.en_US
dc.contributor.authorAssemi, Shoelehen_US
dc.date.accessioned2016-01-08T20:09:50Z
dc.date.available2016-01-08T20:09:50Z
dc.date.issued1992
dc.identifier.urihttp://hdl.handle.net/11693/17386
dc.descriptionAnkara : epartment of Chemistry and Institute of Engineering and Sciences, bBilkent Univ., 1992.en_US
dc.descriptionThesis (Master's) -- Bilkent University, 1992.en_US
dc.descriptionIncludes bibliographical references leaves 80-84en_US
dc.description.abstractSorption behavior of radioiodine on organic rich soil, alumina, chlorite- illite clay mixture, kaolinite and bentonite have bc;en studied using the batch method. was used as tracer. Characterization of samples were done by FTIR, X-ray diffraction spectrometry and particle size distribution by Andreason pipette method. The grain size of the samples used were all below 38/xm and the experiments were performed at room temperature. The aqxreos phase used in all experiments were synthetic ground water with a composition similar to the underground waters of the regions where the samples were obtained. Stock solutions containing tracer, were prepared using synthetic ground- water. Initial concentration of inactive iodide ion in the solutions ranged from 10~®to 10“^ mmole/ml. The influence of contact time, solution/solid ratio, pH of synthetic ground- water, biomass of soil and I~ ion concentration on the sorption of radioiodine on the organic rich soil were investigated. The effect of I~ ion concentration and complexing agents on the sorption behavior of radioiodine on alumina and clay minerals were also studied. A rather slow kinetics was observed for tlie adsor])tion of radioiodine on the organic rich soil, tending saturation within 14 da.ys. It was observed that distribution ratio increased with increasing ratio of the volume of solution to the mass of soil(V/m ratio) and reached a platee.u after V/m=50. Distribution ratio did not change very much by changing the pH of the solution. Comparison of Eh-pH behavior of the solutions with the standard Eh-pH graph of iodine-water system indicated that in the whole pH rcinge, iodine is mostly preseirt in I~ form. To observe the effect of soil biomass soil samples were sterilized by heat and gamma-ray source and the results were found to be much lower than the control sample. Increasing the concentration of iodide ion in the .solution, caused a decrease in Rd. values. Desorption Wcvs ol)served only for low initial iodine concentrations < 1 X I0~^7nmol/ml), for organic rich soil which suggests that at least two sites and/or mechanisms are involved in the sorption. The sorption data were fitted to Freundlich and Dubinin-Radushkevich isotherms. The slope of Freundlich isotherm was found to be less than 1 which indicates the non-linearity of the isotherm. The mean free energy of adsorption was calculated from the slope of Dubinin-Radushkevich isotherm and was found as about 11 k.J/mol. The distribution of sites on organic rich soil was calculated using the Freundlich and Dubinin-Radushkevich constants, considering Cl~ as the competing ion with I~ in the solution. The affinities of sites were found to be about three times higher for Cl~ than I~. Among the clay minerals, the highest Rd value was found for chlorite-illite cla}^ mixture but tlie Rd values found for alumina and the other sanrples were well below those found for the organic rich soil. The sorption data were fitted to Freundlich and Dubinin-Radushkevich isotherms. All the Freundlich isotherms were non-linear (slope<l), except for alumina (slope=0.98), since the alumina sample used was 99% AI2O3. The mean energies of adsorjition calculated for these samples, were in the range of 9-11 kJ/ntol. The .site disiribulion curvois were also obtained for tl samples and the affinities of sites were found to be at least three times higher for Cl~ than I~. Clay samples were ])retreated with comjilexing agents EDTA (Ethelene Diamine Tetra Acetic acid) cuid TPAI (Trimethyl Phenyl Ammonium Iodide). Very low or zero Rii values were found for treated samples.en_US
dc.description.statementofresponsibilityAssemi, Shoelehen_US
dc.format.extentxiii, 84 leavesen_US
dc.language.isoEnglishen_US
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subjectSorptionen_US
dc.subjectDesorptionen_US
dc.subjectRadioiodineen_US
dc.subjectOrganic rich soilen_US
dc.subjectAluminaen_US
dc.subjectClay mineralsen_US
dc.subjectBatch methoden_US
dc.subjectIsothennsen_US
dc.subjectSorption energyen_US
dc.subjectSite distributionen_US
dc.subjectCompeting ionen_US
dc.subjectSoil biomassen_US
dc.subjectComplexing agentsen_US
dc.subject.lccQD547 .A87 1992en_US
dc.subject.lcshAdsorption.en_US
dc.subject.lcshSoil absorption and adsorption.en_US
dc.subject.lcshClay minerals.en_US
dc.subject.lcshSoil microbiology.en_US
dc.titleSorption behavior of radioiodine on organic rich soil, alumina and clay mineralsen_US
dc.typeThesisen_US
dc.departmentDepartment of Chemistryen_US
dc.publisherBilkent Universityen_US
dc.description.degreeM.S.en_US
dc.identifier.itemidBILKUTUPB010915


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