الفهرس 
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Abstract
This work deals with the economic utilization of local available by-product that is saw dust, and using this raw material to isolate the cellulose, after isolation process the antimony as inorganic species was used to impregnate cellulose to produce Cellulose/ HO7Sb3 composite with high ability for adsorption (or removal) of some radionuclides that may be released from nuclear reactors waste.
The impregnation process enhances the chemical and physical properties of cellulose and increases the percent removal of La3+ from 67.5 to 99 %, Co2+ from 43.5 to95 %, and Cs+ from 27.6 to 46 %.
The saw dust is chosen as a raw material for two reasons:
i) It is highly abundant renewable by-product.
ii) It has high mechanical strength.
iii) Cellulose represents (40-50%) of its composition.
The sorption behavior of the element La3+, Co2+, and Cs+ from their chloride solutions on Cellulose/ HO7Sb3 composite, has been studied.
The introduction part of this thesis focuses on the following points:
i) Description of the studied radionuclides
ii) Classification and identification of radioactive liquid waste according to the international atomic energy agency definition.
iii) Techniques used in the treatment of radioactive liquid waste.
iv) Classification of sorbent materials
v) Chemical properties and modification process of cellulose.
The experimental part includes the procedure and methods followed for the preparation and characterization of the used Cellulose/ HO7Sb3. It includes also performing of the adsorption process of the considered metal ions on Cellulose/ HO7Sb3 and investigating selectivity and sorption efficiency for these ions as a function of pH and initial metal concentration as well as other factors such as contact time, temperature and the presence of competing ions. Determination of the thermodynamic parameters (∆Ho, ∆So, and ∆Go), sorption isotherms and kinetics studies have been also reported.
The third part deals with the obtained results and the scientific discussion of these data:
i) The prepared Cellulose/ HO7Sb3 shows a high chemical stability in water and in acid solutions of HNO3 and HCL acids up to 4M.
ii) FTIR analysis indicated the presence of different surface functional groups such as Sb-OH of hydroxyl functional group, and C-H symmetric in the Cellulose/ HO7Sb3.
iii) The SEM photographs show a high surface – area structure of the prepared composite and many active sites for sorption of the metal ions.
The determined optimum conditions for the most efficient sorption process are found to be contact time: 120min, sorbent dosage:0.05gm, initial metal ions concentration in 800ppm and pH of the solution is 5.5 for La3+, pH 6 for Co2+ and pH 6.5 for Cs+.
In general, the removal efficiency of Cellulose/ HO7Sb3 for the used metal ions increases with increasing temperature from 25 to 65 oC.
The presence of either competing ions, such as Na+, Zn2+, Ce3+, or complexing agent, such as EDTA, greatly affect the sorption process negatively.
The distribution studies indicate that the distribution coefficient (Kd) of the studied metal ions are pH - and temperature (T) - dependent. It increases with increasing both pH and T.
The thermodynamic parameters ∆Ho, ∆So, and ∆Go are calculated from the plots relating ln Kd and 1/T. The obtained data indicate an endothermic nature of a spontaneous adsorption process and an increased randomness of the solid – solution interface during the process.
It is to be concluded that, under the same experimental conditions, the removal efficiency and saturation capacity of Cellulose/ HO7Sb3 for the three considered elements are increasing according to the following order:
La3+ > Co2+ > Cs+
The adsorption models (Langmuir, Freundlich, and D-R models) allow predicting the type of the adsorption process and providing information on the strength and values of the adsorption capacity.
Applying the three adsorption models to the present work show that the obtained data are better fitted Langmuir than Freundlich model for both La3+, Co2+ and better fitted to Freundlich than Langmuir for Cs+.
In the kinetic studies, the pseudo first, pseudo second order and intraparticle diffusion kinetic models were applied. It was found that the adsorption of the investigated metal ions follows the second order equation indicating the chemisorption control.
To confirm the efficiency of the prepared Cellulose/ HO7Sb3 in the removal of the studied radionuclides. Radioactive solutions of 140La,60Co, and 137Cs have been prepared and mixed with the composite by measuring the activity before and after sorption the efficiency of the prepared composite has been tested and shows good agreement with the inactive removal percentages.
As an application of this study, the adsorption of the considered metal ions is carried out using the fixed column operation and compared with the data obtained applying the batch experiments.