الفهرس 
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Abstract
Studies of the removal and separation of toxic metal ions have come to play an important role in the scientific and industrial work. In the present work, the main aim is not only synthesis a new inorganic ion-exchanger but also study the exchange behavior of this material to Cs+, Na+, Co e+, Sr24 and Eu3+ from aqueous medium at different reaction temperatures.
Inorganic ion exchangers and absorbents have receiving attention for these purposes because of their strong chemical affinity, high retention capacity and high resistance for ionizing radiation for certain elements. The main goal of this work presented in this thesis is to prepare an inorganic ion exchanger that can be help in various areas such as, toxic waste problem. Also knowing information helping to understand and improve the ion exchange process. To satisfy these purpose silico(IV)titanate is prepared as a new cation exchanger. Silico(IV)titanate is one of the new synthetic ion exchangers materials, double salts of polybasic acids with tetravalent metal types, it is very promising. Characterization of this material using x-ray diffraction, thermal analysis and infrared spectrometry was carried out. Also, the
solubility of this material in water and different acids with various concentrations is determined. The sorption behavior cobalt, strontium, cesium, sodium and europium ions on silico(IV)titanate is conducted. Besides, it involves a study of the kinetics of
exchange.
The work carried out in this thesis is presented in three main chapters, namely; introduction, experimental and results and
discussion.
- The first chapter is the introduction which includes high lights aspects related to the inorganic ion exchangers, their classification and present statues, according to the advantages of the inorganic ion exchangers over the organic resin especially silico(IV) titanate
which we concern in this thesis.
Finally, this chapter includes some aspects and literature survey related to the subject of this thesis.
- The second chapter, experimental, contains detailed information concerning the chemicals and instruments used as well as analytical techniques. Also, a detailed description of the prepared silico(IV) titanate which is used in this thesis is also presented.
- The third chapter deals with the results and discussion and can be summarized in the following two main parts:-
*the first part includes the results of the preparation and characterization of silico(IV)titanate as cation exchanger. The prepared silico(IV)titanate is characterized using x-ray diffraction,
thermal analysis and FT-IR spectroscopy.
It was found that, the prepared silico (IV) titanate has amorphous structure and thermal stability. The solubility data obtained showed the high stability of the prepared ion exchanger towards water, HNO3 up to 6M. Silico (IV) titanate is partially dissolved in HC ?_ 5M. These results indicate that the prepared
silicotitanate has a good thermal and chemical stability compared
with other inorganic ion exchangers.
*The second part includes the results and discussion of the uses of this new prepared SiTi as exchanger for Cs+, Na+, Co2+, Sr2+ and
Eu3+ from nitric acid medium.
The capacity measurement of silicotitanate for the investigated metal ions under different conditions shows that, as the pH of the medium increases, the capacity of the prepared SiTi increases. This may be due to the hydrolysis of W become more easily. By introducing another factor (drying temperature), it was found that the capacities of SiTi dried at different temperatures for the investigated metal ions at o.1 M are studied. These results indicted that the capacity of the prepared SiTi decreases with increasing the drying temperature from 50 to 400 °C. This may be due to loss the free water.
The distribution coefficient measurements for the investigated metal ions on SiTi show that, the relation between log kd and pH gives a straight lines with slope less than the valence of the cations. This deviation can be explained by the exchange of nitrate groups with the hydroxyl groups of the exchanger, where the uptake of nitrate groups and releasing the hydroxyl groups leads to increase in the pH of the medium than the actual pH permitting the deviation from the ideal behavior to occur. The investigated metal ions actually sorbed from the nitrate medium as cations will replace the hydrogen ions in the silico (IV) titanate exchanger.
The effect of concentration on the sorption of cesium, sodium, strontium, cobalt and europium (sorption isotherms) is studied at different reaction temperatures (25, 40 and 60 °C). These results proved that the sorption of investigated metal ions is endothermic process since as the reaction temperature increases, the uptake of these ions increases. Also, the adsorption of cations on silico. (IV) titanate was analyzed by use of the Freundlish adsorption
isotherms.
The kinetic studies which are performed on the sorption of the studied metal ions from nitrate medium on silico (IV) titanate, after providing the conditions that permit the particle diffusion mechanism to be the main mechanism, give the following results;
•On studying the particle size effect, it appears that as the particle diameter decreases, the rate of the exchange of cations on silico (IV) titanate increases.
•The rate of the ion-exchange increases as the reaction temperatures increases.
•The effect of metal ions concentrations on the rate of the ion exchange were carried out by using different concentrations from the investigated metal ions. The results obtained
showed that, the rate of exchange dose not depend on the solution concentrations.
•The rate of ion exchange increases as the drying temperatures increases.
•The activation energy, diffusion coefficient and the entropy are calculated at different conditions at which the reaction was performed by applying the Arrhenius equation.