الفهرس 
Chapter I Introduction And Literature ReviewOnly 14 pages are availabe for public view
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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, properties and their discovery of the rare earth elements. 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- Methods for determination of The Rare Earth Elements 8- The several applications involving the use of the rare earth elements were presented. 9. Global production and consumption of rare earth elements 10. Rare earths prices 11- uranium occurrence , properties, uses, production. 12-Different methods for recovery and separation of uranium from solutions . 13- Nano materials preparation and its advantage Chapter II (Experimental): This chapter contained different chemicals used in this study as well as the methods utilized for determination of uranium (VI), rare earths and other ions in solution . It contained detailed description for the instrumentation used for determination of uranium , rare earth and Instruments used for material characterization. Experimental techniques used during this work. The applied ion exchange technique batch systems method was also described. 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 from monazite sample. Also this chapter contain experiments and techniques that were used in preparation and characterization of magnetic nano materials and elution of uranium ion and regeneration of magnetic hydroxyapatite Chapter III (Results and Discussions): CHAPTER THREE This chapter is divided into two partitions PART 1:
Discuss the successful adsorption procedure for uranium from rare earths sulfate liquor produced from Egyptian crude monazite by using lewatit mono plus M500 adsorbent and the studied relevant factors have actually been optimized. It was performed using one g adsorbent in rare earths sulfate liquor (100 ml) contaminated with 200 mg/L uranium at room temperature for 30 min and pH is 1.8. Under these conditions, the achieved uranium capacity was attained 40.65 mg/g. The loaded uranium was afterward completely eluted using 25 ml of 2M NaCl / 1M HCl solution using 30 min contact time for each g of adsorbent. The pseudo second order kinetic model was found to be the best fit the experimental results of uranium adsorption by the lewatit mono plus M500 from the rare earths sulfate liquor with a correlation coefficient very close to unity. uranium loading has been decreased with increasing temperature may be due to the exothermic nature of U (VI) adsorption in a manner to be favored at room temperature. The uranium adsorption at room temperature (25 ºC) reached 91.2% and decreased down to reach 51.7% at 55 ºC. The enthalpy change is −61.43 kJ/mol indicating its exothermic nature and the reaction is spontaneous. Finally, a marketable product of sodium diuranate was prepared. The rare earths were precipitated from the effluent by oxalic acid to produce REEs oxalate .A proposed pilot unit is suggested for pure salable or REEs production ready for further single REEs separation processes in addition to uranium product. PART 2: studying the nano-sized hydroxyapatite preparation by the wet chemical route method then the magnetic hydroxyapatite Nanocomposite was successfully prepared using a simple , fast microwave combustion method, a low total period of process and high degree of product purity is related . The addition of urea as a combustion fuel. This method is the fastest for its synthesis. The preparation of novel nano-magnetic hydroxy apatite to be used as adsorbent for uranium ion adsorption from the aqueous solution.
The BET characterization showed that the specific surface area ,pore volume, and pore diameter of nano particles were 90 m2/g, 0.2498 cm3/g, and 20 nm, respectively. The adsorbent showed high sorption capacity for U(VI) and could be easily separated from aqueous solution by the application of an external magnetic field . Adsorption of Uranium was studied under different factors such as initial concentration, adsorbent amount , pH of solution govern the adsorption of uranium on MHAP, dose of adsorbent and effect of temperature . Adsorption of U(VI)ion is maximum for pH =5 and also adsorption increases slightly with increase in the adsorbent amount. The high correlation coefficient is obtained for Longmuir model hence it was best fitted isotherm under the experimental conditions (pH 5, contact time 2 h, and adsorbent amount 0.025 g/L, adsorbate concentration 200mg/L and ambient temperature). The isotherm adsorption data fit well with the Langmuir model, and the kinetic data fit well with the pseudo-second-order model. The recovery of uranium ion and reusability of adsorbent proved the excellent regeneration property. The mechanisms of adsorption on MHA could be due to the electrostatic attraction, ion exchange, dissolution/precipitation, and surface complexation. Ion exchange and surface complexation are responsible for the adsorption process. According to the data, prepared adsorbent can be considered very promising for the removal and recovery of uranyl ion on account of high adsorption capacity, economic and environmental benign properties and also magnetic separation advantage.