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Abstract The present thesis was composed of three main chapters, each of which can be summarized as follow: Chapter I (Introduction): Chapter one is an introduction to discuss, a full literature survey concerning the rare earth elements and a special focus on uranium was introduced. The main points that have been discussed through this chapter can be summarized as follow: 1- The definition, source uses of the rare earth elements and their discovery. 2-Exploration of the different minerals containing rare earth elements, their distribution and reserves all over the world. 3-The properties of the rare earth atoms and ions, which include the electronic configuration, position in the periodic table, oxidation states, magnetic and spectral properties. 4-The different methods for the physical and chemical processing of the rare earth ores were presented and reviewed. 5- Focusing on the resources of rare earth ores in Egypt, and discussing the physical and chemical processing techniques utilized in Egypt for the processing of monazite mineral derived from Egyptian black sands. 6- Reviewing of the methods concerning the separation of rare earth elements as a group and individually. 7- The several applications involving the use of the rare earth elements were presented. 8- The abundance of uranium, properties, uses, uranium extraction methods are discussed as well as a brief outline of the chemistry of ion-exchange of uranium and the importance of exchanger and techniques used. Chapter I1 (Experimental): This chapter contained different chemicals and reagents used in this study as well as the methods utilized for determination of uranium (VI), rare earths. It contained detailed description for the instrumentation and experimental techniques used during this work. The applied ion exchange technique using fixed bed and batch systems method was also described. This chapter contains the preparation of solutions The section also gave the details of experimentation used in studying the uptake behavior of the resins towards U (VI) form aqueous solution as well as fiom monazite sample. The utilized chemicals, reagents, materials, instruments and equipments were stated. We can summarize the experiments which have been made in this work as follows: 1-Sulphuric acid digestion procedure for monazite was carried out in order to get a rare earth, thorium and uranium cakes. 2-Preparation of rare earth hydrous oxides, thorium and uranium oxides cake fiom Egyptian monazite 3- Demonstration of the analytical procedures for determination of rare earth elements, thorium and uranium in different media. 4-Batch experiment for sorption on Amberlite IRA-402C1 5-Fixed bed column experiment for uranium sorption on Amberlite IRA- 402C1. Chapter I11 (Results and Discussions): CHAPTER THREE The results of experimental work were declared and discussed can be summarized as follows: Experimental studies of the sorption kinetics of uranium anion fiom its Solution on amberlite IRA-402C1 (Amb- IRA-402C1) sorbent was achieved at batch and flow systems. In the batch process results of uranium separation by ion exchange resin namely Amberlite IRA-402C1 was discussed herein.Factors affecting the extraction of uranium such as pH, contact time,temperature, initial uranium concentration were indicated . The pH of solution had dramatic effects on the uptake of U by Amb- IRA-402C1. It was found that pH in the range of 1.5-2 was proper conditions of U sorption at the present experimental set. It was found that the extraction efficiency of uranium reach to maximum at pH 1.75. Shaking time of 3 5 min. is found to be sufficient for reaching equilibrium. The obtained data were found to obey Langmuir and Freundlich isotherms. Adsorption of uranium ions through Amberlite IRA-402C1 resin in a packed bed column was a clean economic feasible technique for removing metal ions fiom a solution. The process allowed treatment of a given volume of effluent by using a minimal mass of adsorbent which concentrates maximal content of metal. The adsorption breakthrough curves obtained at different flow rates indicate that an increase in flow rate decreases the volume treated until the breakthrough point and therefore decreases the service time of the bed. Lower removal capacities were observed, probably due to the fact that contact times were insufficient for the adsorption equilibrium to develop between the resin and the metal ions. The proper ranges of concentration for the sorption of uranium upon Amber lite IRA-402-C1 was 300-500 ppm, flow rate lml Imin, bed hight 16 cm or more and 1.2 cm radius of the column under the attained equilibrium ,kinetic and thermodynamic parameters which gathered fiom the previous batch process. Partially mass balanced flow diagram ,hypothetical unit construction ,and recommendation for the decontamination process was presented finally. |