الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The nuclear energy industries have been grown during the past several years and continuing growth is predicted over the next few decades during which time nuclear power is expected to become a major source of energy. Although considerable effort is being made to minimize the release of the increasing amounts of radioactive waste into our environment, it is evident that the potential for radioactive contamination will continue to grow. So, the main target of this work was concern with the study of the extraction of uranium from its solutions those produced from different industrial processes as an undesirable waste by using the commercial materials such as natural zeolite (clinoptilolite). The present work carried out in this thesis, is classified into three main chapters (introduction, materials & methods, and results & discussion). The contents of each chapter are presented as follows:
Chapter 1: Introduction
The main points in this chapter include: sufficient information about the different sources of uranium in natural as well as a briefly scientific background on its chemical and nuclear properties. It includes also, information about the mechanism isotherm, and thermodynamics parameters of the adsorption methods that used in the treatment of different uranium wastes. It contains general aspects on the origin and formation of the clinoptilolite as well as natural zeolite and its important rule on the adsorption processes. This chapter concerns with a full literature survey on local and international published papers for the utilization of the clinoptilolite and zeolite in many industrial applications as well as the different previous methods those used in the extraction and reduction of the amount of uranium from major undesirable wastes those produced from different industrial processes. Also, the end of this chapter includes the overall aim of the present work.
SUMMARY
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Chapter 2: Materials and Methods
This chapter includes the preparation of all required samples for analysis, as well as chemicals, reagents materials, apparatus, instruments and equipments used in the experimental work. It includes also, the full description of the different spectroscopic instruments those have been used, which are: scan electron microscopy (SEM-EDX), X-ray diffraction (XRD), X-ray fluorescence (XRF) as well as FT-IR-spectrometry. The analytical methods for sample preparation, experimental procedures for adsorption processes, pretreatment investigations, leaching processes and stripping studies are also presented associated with the description of best optimum conditions for each process.
Chapter 3: Results and Discussion
This chapter is subdivided into the following six main parts:
Part One (Preparation of the Clinoptilolite)
This part covers the spectroscopic characterizations and the chemical and physical treatment studies of the clinoptilolite. The spectroscopic characterization indicated that, the measurements of XRD, XRF and FT-IR indicated that the main phase composition of clinoptilolite under study. The chemical treatment processes were used with complete discussion of the preparation of thermal clinoptilolite using the best conditions. The physical treatment was depended on the fractionation of clinoptilolite into coarse and fine size. The physical approach indicated that the fine particle size of 53μm (compared to those found in bulk) was the best one for giving the optimum adsorption of uranium from different studied wastes. The good results of the treatment studies were confirmed by the application of clinoptilolite in this particle size for leaching of uranium from different concentrations (100, 500, 1000, 5000 ppm) of standard solution.
Part Two (Adsorption Studies)
This part deals with the complete description of the mechanism and isotherm of adsorption processes with respect to determine the thermodynamics parameters of applications of clinoptilolite on the removal of uranium from the studied concentrations of the (uranyl nitrate) standard solution.
SUMMARY
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Part Three (Distribution of Uranium in Different wastes)
This part deals with the characterization and chemical analyses of different uranium wastes for major and trace components. The spectroscopic characterizations were carried out to identify the composition of phosphogypsum compound. The complete chemical dissolution was carried out using HNO3 as well as H2SO4 under optimum conditions for the wastes from Abu-Zenima & Abu-Rusheid project (waste-A & waste-B) as well as phosphogypsum (waste-C) respectively. The results indicated that, on the addition of 500 ml of 4M HNO3 to 30 g of waste-A at 60°C for 30 minutes give rise to extract 96.5%, while 94.7% was achieved in case of waste-B when 500 ml of 6M HNO3 was mixed with 30g of the studied waste at 40°C for 45 minutes. The uptake of 96.3% was obtained after addition of 15g phosphogypsum to 500 ml of 7M H2SO4 at 60°C for 45 minutes.
Part Four (Uranium Waste Management)
This part deals with the leaching of uranium using natural and thermal clinoptilolite, in which several factors have been considered included: effect of time, temperature, revolution of speed, mass/volume, and sequential chemical treatment. The results indicated that, under the addition of 25g of thermal clinoptilolite per 500 ml waste-A at 45°C for 45 minutes with 200 rpm, 91 % of U was adsorbed after second step. In case of waste-B, 93% of U was extracted after second step by reaction of 20g with 500ml of the studied waste at 45°C for 45 minutes with 250 rpm, while about 97% of U was recovered from PG at 45°C when 25g was agitated with 500 ml PG ml 200 rpm for 30 minutes after two steps.
Part Five (Stripping Processes)
This part includes the factors that affect on the stripping process such as; effect of stripper type, shaking time, aqueous/solid ratio, and stage number. The results show that, the best aqueous/solid ratio was 2:1 for the stripping processes and 30 minutes was the best shaking time using 0.5 M of (NH4)2CO3. The stripping percent of 95.8, 87.6, and 78.1% was achieved for waste-A, waste-B, and waste-C respectively after fourth stage.
Part Six (Flow Sheets and Economic Costs)
Finally, the total cost for production of decontaminated product was studied; also the recommenced flow sheets for the overall treatment process and applications were diagrammatically established.