الفهرس 
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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.