الفهرس 
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Abstract
The twin important nuclear elements, thorium and uranium are the corner stone of the (industrial) nuclear technology and consequently the production of nuclear fuel used in nuclear power plants which has a return on the production of huge energy capable of developing any country due to its application as an efficient fuel for electric power plants. Accordingly, it is a strategic issue where their exploration in their bearing rocks and hence their exploitation for production of nuclear grade yellow cake (highly concentrated uranium) is an important step in the nuclear fuel cycle. So, their accurate determination using several advanced and single techniques with economic procedures will be of great prominence for a precise and accurate evaluation of their occurrences in certain areas.
Problems encountering the spectrophotometric technique in rock analysis are mainly referring to spectral interference which enhances the absorbance value giving out incorrect (high) concentration.
To solve these problems, the segregation including coprecipitation, solvent extraction, electrodeposition, ion-exchange…etc has been used in the analytical chemistry laboratories for their precise and accurate determination. Solid phase extraction (SPE) is one of the efficient preconcentration-differentiation procedures used and a preferable choice in the analytical chemistry in common, due to its simplicity, selectivity, commonly used equipments, ease of operation, and the multiple usages of adsorbents for numerous separation and preconcentration cycles without deprivation in the metal ion sorption capacity have made their use popular.
The present study is mainly concerned towards the development of simple and accurate spectrophotometric method for uranium and thorium determination in different rock types bearing uranium and thorium using both EIR(alizarin red S dyes impregnated with amberlite XAD 2010) and (chrome azurol S dye impregnated with Amberlite XAD 2010), then direct spectrophotometric determination of uranium and thorium. The two methods depends on the adsorption of uranium and thorium on EIR (ARS- XAD2010) and (CAS-XAD2010) and were optimized by studying several parameters to reach the best conditions of adsorption efficiency.
This work was first directed towards the preparation of both ARS impregnated with XAD 2010 and CAS impregnated with XAD 2010, then optimizing the relevant factors affecting both adsorption and elution of uranium and thorium.
The present thesis was divided into five chapters and a brief summary and conclusions which are presented in the following paragraphs.
Chapter I: Introduction
Includes an introduction on the history of uranium and thorium, their abundance in earth crust, the most important thorium and uranium minerals, their physical and chemical properties, compounds, uses, isotopes, applications and their effect on human health.
Chapter II: Literature Survey
Includes a literature survey on different methods of uranium and thorium determination; gravimetric, volumetric, spectrometric, ion exchange and spectrophotometric methods.
Chapter III: Experimental
This chapter contained different chemicals used in this study as well as the methods utilized for determination of uranium (VI), thorium (IV) and other ions in solution. It contained detailed description for the instrumentations used for determination of uranium, thorium and that used for material characterization.
The applied batch adsorption technique was also described. This chapter gave the details of experimentation used in studying the uptake behavior of the resins towards U (VI) and Th(IV) from aqueous solution as well as from certified and different rock samples.
Chapter IV: Results and Discussion
This chapter includes the results and discussion of several parameters studied for the optimization of uranium and thorium adsorption using both ARS-XAD 2010 and CAS-XAD 2010. It is divided into two partitions.
Part I: Studied Parameters for Optimization of Uranium and Thorium Adsorption on EIR (ARS-XAD2010)
The successful adsorption procedures for uranium and thorium by using the synthesized EIR (ARS-XAD 2010) and studied relevant factors have actually been discussed.
A combination between the separation of U(VI) and Th (IV) ions and its spectrophotometric procedure by a high stable EIR was described.
(1) The new EIR was prepared by impregnating alizarin red S onto Amberlite XAD-2010 beads.
(2)The maximum sorption capacity of the interested metal ions was acquired by conducting a fixed EIR (ARS/ XAD-2010) weight (0.1g) with 50 ml of each uranium at pH 4 and thorium at pH 2 ions solution in perchloric acid (0.01M) for 10 minutes contact time at room temperature.
(3)Langmuir isotherm model has better fitting experimental data with a maximum adsorption capacity of 19 mg/g for U (VI) and 17 mg/g for Th (IV).
(4) The adsorption process of each metal ion by synthesized Alizarin Red S impregnated XAD-2010 showed an exothermic pseudo-second-order adsorption process.
(5) The loaded metal ions were afterward completely eluted using one mole of 10 ml HCl solution using 10 min contact time.
(6) High tolerance limits for several metal ions on Alizarin Red S -impregnated XAD-2010 were calculated and gave high tolerance limit.
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Part II: Studied parameters for optimization of uranium and thorium adsorption on EIR (CAS-XAD 2010)
This part discussed successfully the adsorption procedure for uranium and thorium by using the synthesized EIR (CAS-XAD 2010) and studied relevant factors.
(1) The new EIR was prepared by impregnating chrome azurol S onto Amberlite XAD-2010 beads.
(2) The maximum sorption capacity respect to interested metal ions was acquired by conducting a fixed EIR (CAS/ XAD-2010) weight (0.1g) with 50 ml of each uranium and thorium ions solution at pH 3 in hydrochloric acid 0.05 M for 15 minutes contact time at room temperature.
(3) Langmuir isotherm model has better fitting experimental data with a maximum adsorption capacity of 22.5 mg/g for U (VI) and 24.25 mg/g for Th (IV).
(4) The adsorption process of each metal ion by synthesized chrome azurol S -impregnated XAD-2010 showed an exothermic pseudo-second-order adsorption process.
(5) The loaded metal ions were selectively eluted using 1 M of 10 ml HCl solution for Th (IV) and 1 M of 10 ml ammonium di hydrogen phosphate solution for U (VI) using 10 minutes contact time.
(6) The tolerance limits for several metal ions on chrome azurol S -impregnated XAD-2010 were calculated and gave high tolerance limits.
Chapter V: Applications
The proposed methods were applied for preconcentration and determination of U (VI) and Th (IV) in different samples including certified and geological materials to verify their applications and validations.
from the obtained results, it can be observed that applying adsorption of uranium and thorium on EIR (ARD-XAD and (CAS-XAD 2010) using the proposed optimized methods were accurate, simple and cost-effective for analyzing ore samples bearing uranium and thorium.