الفهرس 
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Abstract
Inorganic ion exchange materials play an important role in the last decays in the fields of industry, medicine,agriculture and nuclear technology due to their stabilities towards thermal and radiation and their resistance to chemical attack.
The most important property of inorganic ion exchangers enabling their use in the various chemical separation is the selectivity.
The work carried out in this thesis is summarized in to three main parts; namely, introduction, experimental and finally results and discussion.
1. Introduction:
This chapter includes definition and toxicity of heavy metals, historical back ground of inorganic ion exchangers, their classification and present status according to the advantages of the inorganic ion exchangers. Theory for the ion exchange studies, ion exchange equilibrium and selectivity, sorption isotherms, kinetic measurements and a literature review related to the different inorganic ion exchangers.
II. Experiment
This chapter includes the chemicals used and their purity, the method of preparation of Tin Vanadate (SnV) and Titanium Potassium Vanadate (TiKV) as well as the instrumentation, the analytical techniques and the procedures used in this thesis.
III. Results and Discussion:
This chapter deals with the results and discussion which are divided into five main parts.
1. Preparation and characterization of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV):
Tin Vanadate (SnV) was prepared by adding aprecipitate of (SnCL4) to (NaVO3) with stirrer by using magnetic stirrer to obtain homogenous precipitate. The precipitate was filtered, washed several times with deionized water. The precipitate was dried at 50oC in an electric drying oven, grained and sieved for different mesh sizes and stored at room temperature.
Titanium Potassium Vanadate(TiKV) was prepared by adding aprecipitate of (TiCL4) to KCL and(NaVO3) with stirrer by using magnetic stirrer to obtain homogenous precipitate. The precipitate was filtered, washed several times with deionized water. The precipitate was dried at 50oC in an electric drying oven, grained and sieved for different mesh sizes and stored at room temperature.
The prepared materials were identified by using different techniques, such as, chemical stability, IR-spectra, X-Ray diffraction as well as TG and DTA thermal analysis.
Chemical stability of SnV and TiKV were studied in water, nitric acid and hydrochloric acid [0.001,0.01,0.1,1,3,5M].and we find that, SnV and TiKV are stable in H2O, nitric acid and hydrochloric acid up to 0.1M, and the solubility increased with the increasing acid concentration.
The infrared spectrum of prepared SnV and TiKV samples were displayed in the IR range 400-4000 cm-1.
X-ray diffraction (XRD) patterns obtained for the prepared samples are represented in Figs. (3 and 4) and manifested that the prepared samples dried at 50oC have amorphous structure. In addition,the crystalline character of the samples was increased with heating temperature from 50o to 600oC.
The thermal analyses of SnV and TiKV samples from the various thermograms, it can be confirmed that samples show high thermal stability and the water content will calculated.
2. Equilibrium Studies:
1. Distribution coefficients:
The distribution coefficient of the studied cations (Fe3+, Co2+, Cu2+, Zn2+, Cd2+, Cs+and Pb2+ ) was investigated on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) at different pH values at 25oC±1oC. The obtained results showed the Kd values increase with increasing the pH of the solution. from the plots of log Kd vs. pH, (Fe3+, Co2+, Cu2+, Zn2+, Cd2+, Cs+and Pb2+ ) ions were found to deviate from the ideal ion exchange reaction mechanism. The selectivity order of the investigated cations on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) in the same conditions has the following sequence;
Pb2+ > Cs+ > Cu2+ > Zn2+ > Co2+ > Fe3+ > Cd2+
The distribution coefficient values of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV)for the studied metal ions were compared to the other ion exchange materials.
The effect of reaction temperature on the adsorption of Fe3+, Co2+, Cu2+, Zn2+, Cd2+, Cs+and Pb2+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate (TiKV) samples were carried out in the temperature range 25-65±1oC, the distribution coefficient (Kd) of Fe3+, Co2+, Cu2+, Zn2+, Cd2+, Cs+and Pb2+ on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) increased with increasing temperature from 25oC to 65oC and the thermodynamic parameters (ΔHo, ΔSo and ΔGo) for the adsorption of Fe3+, Co2+, Cu2+, Zn2+, Cd2+, Cs+and Pb2+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) were calculated.
2. Ion exchange capacity:
The ion exchange capacities of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) samples for Fe3+, Co2+, Cu2+, Zn2+, Cd2+, Cs+and Pb2+ions has been determined as a function of pH with constant ionic strength (0.1). The obtained results showed that, the capacity of the studied metal ions increases by increasing the pH. The ion exchange capacity of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) for Pb2+ ion at different drying temperature has been determined and showed that, Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) show decrease in its capacities by increasing the drying temperatures from 50oC to 850oC.
The capacity of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) for Pb2+ ion was determined at different metal ion concentration and the results showed that at low concentration from Pb2+ metal ions (0.01 M up to 0.05 M) the capacity of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) was increased tremendously, but at height concentration (0.075 M up to 0.15 M) slightly increased for the capacity was observed (nearly constant).
3. Kinetic Studies:
The kinetics of exchange of Co2+,Cd2+,and Cs+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) are studied as a function of Concentration,particle diameter , Drying temperatures and reaction temperatures (all experiments were carried out under particle diffusion control as a limited batch techniques only).
The results showed that, the rate of exchange of different metal ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) is independent of metal concentrations in solutions up to 5x10−2 M. The rate increases with decreasing the particle size. Also, the rate increases with decreasing the dringing temperature of the exchange materials, while it increases with increasing the reaction temperature . The values of the effective diffusion coefficients (Di), entropy of activation (ΔS*) and energy of activation (Ea) for Co2+,Cd2+,and Cs+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) have been determined and are compared with the values reported in literature.
The average values of diffusion coefficients (Di) of Co2+,Cd2+,and Cs+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) of different particle diameters were calculated. The obtained results showed the diffusion coefficients calculated for larger particle sizes are slightly higher. Also, the average values of diffusion coefficients (Di) of Co2+,Cd2+,and Cs+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) dried at (50, 200 and 400◦C) were calculated. The obtained results showed that there is an appreciable decrease of self-diffusion of Co2+,Cd2+,and Cs+ with an increase in the drying temperature of Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) from 50 to 400◦C. on contrast, the values of Di increase with increasing the reaction temperatures from 25 to 65oC.
The activation energy for the investigated metal ions (heating at 50 ◦C) was calculated and has the order:
Cs+> Co2+> Cd2+
Negative values of entropy of activation (ΔS*) were obtained for Co2+,Cd2+,and Cs+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) samples at all operative conditions.
4. Sorption isotherms:
the results suggest that the adsorption of the studied metal ions (Co2+, Cd2+and Cs+ ions) on Tin Vanadate(SnV) and Titanium Potassium Vanadate (TiKV) is favorable for the Freundlich isotherm more than Langmuir and D-R isotherm.
Conformation of the experimental data with Freundlich isotherm indicate the monolayer coverage of sorption surfaces and assumes that sorption occurs on a structurally heterogeneous adsorbent and all sorption sites are energetically identical. from the above discussion all the studied elements ( Co2+, Cd2+and Cs+) are physically adsorbed.
5. Column technique:
In column investigation, when Tin Vanadate(SnV) and Titanium Potassium Vanadate (TiKV) are used as ion exchangers for treatment of industrial waste water, the solution is percolated through affixed bed of Tin Vanadate(SnV) and Titanium Potassium Vanadate (TiKV) . The column is operated downflow by running the solution through the exchanger from top to bottom. The solution which enters the column is called the influent, and the filtrate from the column is called the effluent.
The procedure may be shown with curves of the ratio C/Co between the effluent and influent concentrations as function of time or effluent volume.