الفهرس 
Chapter1 IntroductionOnly 14 pages are availabe for public view
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Abstract
The present thesis is composed of three chapters; each chapter can be summarized as follow : Chapter 1 : Introduction The main point that have discussed through this chapter can be summarized as follow : a- General introduction about the heavy metals, its toxicity and the effects of these metals on living organisms. b- Rare Earth Elements and titanium from occurrence, uses and applications c- The several methods used for separation and pre-concentration of different metal ions prior to their determination such as co- precipitation, solid phase extraction, ion exchange resins, flotation, liquid-liquid extraction and cloud point extraction. d- The detailed survey on the phase separation in cloud point extraction and its advantages as a promising, viable and benign alternative to the current classical separation method such as, simplicity, cost saving, speed, high pre-concentration factor and no waste generation as practiced in the liquid extraction tools. e- The different types of surfactants which used in cloud point extraction. f- Formation of micelles and their different forms. g- The different parameters affecting on the extraction efficiency of cloud point extraction system including pH, chelating agent, concentration and type of surfactant, temperature, equilibration time and ionic strength. h- The different types of ligands which previously used in cloud point extraction. i- The applications of cloud point extraction for separation and pre- concentration of different analytes such as, organic compounds, biomaterials, nanoparticles and metal ions. Chapter 2 : Experimental Includes a list of reagents, stock solutions along with the analysis, physical measurements and instruments such as UV-Vis. As well as adscription of the preparation of the ligand and its metal complexes, studding the different parameters for the optimization of CPE procedure, pre-treatment of real samples and applications of the proposed method for separation, pre-concentration and determination of metal ions from different media (geological and water samples, simulated reference material, synthetic mixtures). Chapter 3 : Results and discussion It divided into 5main parts. Part (1) : A Micro Mixed Micelle-mediated Pre-concentration Procedure for Spectrophotometric Determination of Fe(III) in water and blood Samples. The absorption spectra of Zincon and Fe(III) –Zincon complex was investigated at 514 and 603 nm. The main factors affecting mixed micelle-mediated extraction efficiency were studied and optimized as follow : A pH 5 was chosen as the optimum pH for separation and determination of Fe(III). The optimum condition of Zincon concentration was 0.1×10-3 mol L-1. 1.0×10-4 mol L-1 concentration of CTAB was used as optimal. The optimum condition of Triton X-114 concentration was 0.05 % (v/v) during the study. The effect of the addition of various salts (NaCl, KI, and Na2SO4) on the recovery of Fe(III) by the under-investigated method was studied and the results showed that the addition of Na2SO4 provided a higher recovery for Fe(III) than the NaCl and KI. The best centrifugation rate at 4000 rpm and time at 5 min. Effect of the potentially interfering ions was summarized as most species did not interfere even at high concentrations, indicating the applicability of the method for analysis of Fe(III) in samples with different matrices. However, Co2+, Cu2+ and Ni2+ showed interferences at 100 folds higher. These interferences can be eliminated by addition of 0.05% (w/v) CN-. At optimum conditions, the linear range was 10- 1000 µg L-1 with a detection limit of 3.1 µg L-1 was achieved for uranium separation using visible spectrophotometry. The accuracy of the procedure was verified through recovery experiments in water, blood and simulated high level waste samples and the % recovery is between 95.0-99.2%. Part (2) : Determination of trace Ni2+ by CPE using Zincon as a chelating agent. bThe absorption spectra of Zincon and Ni2+-Zincon complex was investigated at 514 and538 nm. The main factors affecting cloud point extraction efficiency were studied and optimized as follow : -A pH 7 was chosen as the optimum pH for separation and determination of Ni2+. -The optimum condition of Zincon concentration was1.0×10-4 mol L-1 . 1.0×10-4 mol L-1 concentration of CTAB was used as optimal. -The optimum condition of Triton X-114 concentration was 0.07 % (v/v) during the study. -The effect of the addition of various salts (NaCl, KI, KNO3 and Na2SO4) on the recovery of Ni 2+by the under-investigated method was studied and the results showed that the addition of Na2SO4 provided a higher recovery for Ni2+ than the NaCl , KI and KNO3. -The best centrifugation rate at 4000 rpm and time at 5 min. -Effect of the potentially interfering ions was summarized as ; most species did not interfere even at high concentrations, indicating the applicability of the method for analysis of Ni 2+in samples with different matrices. However, Al3+, Cu2+ and Zn2+ showed that interferences at a concentration of 200 times higher than Al3+ concentration. The interferences of, Al3+, Cu2+ and Zn2+ can be eliminated by addition of 0.1% (w/v) EDTA. -At optimum conditions, the linear range was 5- 3000 µg L-1 with a detection limit of 1.05 µg mL-1 was achieved for Al3+separation using visible spectrophotometry. The accuracy of the procedure was verified through recovery experiments in water, blood, rocks and soil samples and the % recovery is between 95.0-98.6%. Part (3) : Determination of copper in biological and geological samples by CPE using Zincon as a ligand and ICP-OES as an analyzing technique. -The absorption spectra of Zincon and Copper–Zincon complex were investigated at 512 and 570nm. -The main factors affecting cloud point extraction efficiency were studied and optimized as follow : -The optimum pH for separation and determination of Cu2+ was chosen as pH 7. -The optimum condition of Zincon concentration was 1.0×10−4 mol L-1 .The optimum concentration of CTAB was used at a 1.0×10-4 mol L-1. -The optimum condition of Triton X-114 concentration was 0.05 % (v/v) during the study. -The effect of the addition of various salts such as (KI, KNO3, NaCl and Na2SO4) on the recovery of Cu2+by the under-investigated method was studied and the results showed that the addition of Na2SO4 resulted a higher recovery for Cu2+than the NaCl, KI and KNO3. -The best centrifugation rate at 4000 rpm and time at 10 min. -Effect of the potentially interfering ions was summarized as follow ; most species did not interfere even at high concentrations, indicating the applicability of the method for analysis of Cu2+in samples with different matrices. However, Co2+and Al3+ showed interferences at 250 folds higher and Ni2+ showed interferences at 400 folds higher. These interferences can be eliminated by addition of 0.1% (w/v) EDTA. -At optimum conditions, the linear range was 5-1000 µg L-1 with a detection limit of 1.45 µg L-1 was achieved for Cu2+separation using visible spectrophotometry. The accuracy of the procedure was verified through recovery experiments in water, blood, rocks and soil samples and the % recovery is between 98.5-100%. Part (4) : Spectrophotometric determination of Al3+ by CPE using Zincon as a ligand. The addition of Al3+ to Zincon results in a color change due to the formation of Al-Zincon complex with a maximum absorbance at 512 and 590 nm. Optimization of the CPE procedure of determination of Al3+ as follow ; -The maximum absorbance was obtained at pH 5.0. So pH 5.0 was selected for the subsequent studies. -The optimum concentration of Zincon was 1.0×10-4 for the determination of Al3+. -The concentration of Triton X-114 was used as optimal is at 0.05 % (v/v). -The optimum concentration of CTAB was 1×10-4 mol L-1 . -At 45˚C was chosen for the equilibration temperature and incubation time of 10 min is adequate to achieve the highest extraction efficiency. -A centrifugation time of 5.0 min was selected and the rate of centrifugation was 4000 rpm. -Effect of the addition of different salts on the recovery of showed that the addition of Na2SO4 provided a higher recovery for Al3+ than the NaCl and KI. -The presence of large amounts of commonly occurring cations and anions as well as some masking agents has no obvious influence on the separation and determination of Al3+ under the optimum work condition, Fe3+ showed interferences at 150 folds higher and Ni2+ showed interferences at 100 folds higher. These interferences can be eliminated by addition of 0.1% (w/v) EDTA. -At optimum conditions, the linear range was 5- 500 µg L-1 with a detection limit of 1.5 µg L-1 was achieved for Al3+ separation using UV-visible spectrophotometry. Part (5) : A Tetracyclein (TC) for CPE of separation of Ti(IV), Sc(III) and Sm(III) prior to their determination by ICP-OES Spectrophotometric determination of by CPE Ti(IV), Sc(III) and Sm(III) using TC as a ligand. The addition of Ti(IV), Sc(III) and Sm(III) to TC results in a color change due to the formation of complex with a maximum absorbance at 464 nm for Ti(IV), 419nm for Sc(III) and 396 nm for Sm(III). Optimization of the CPE procedure as follow : PH 3, 6, 7 was used for the all metal ions Ti(IV), Sc(III) and Sm(III) prior to their determination by ICP-OES. -The optimum concentration of TC is 1.0 × 10-4 mol L-1 for the these metals ions. -A concentration of 0.1% (v/v) of Triton X-114 was chosen for following experiments. -The presence of 0.1 mol L-1 of Na2SO4 makes the system cloudy without the need of heating and therefore make the extraction process more rapid and energy saving for all metal ions. -The results for these metals indicate that centrifugation at 4000 rpm for 5 min recover all studied metal ions quantitatively. -The stability constants were found to be 7.0 × 105, 2.3 × 105, 1.9 × 106 and 3.2 × 105 L mol−1, respectively, indicating good stability of the complexes. -The results indicated that most concomitant ions had no interference electrolytes on the determination of these metals by the presented CPE procedure. This indicates the possibility of applying the procedure for analysis of real samples of rock matrices. -At optimum conditions, the linear range were 5-3000, 0.5-150 and 0.3-100 for Ti4+, SC3+and Sm3+ respectively and LOD for for these metals were 0.88, 1.5 and 0.23 respectively. -The reliability of the suggested procedure, it was applied for pre-concentration of these metals from real samples such as water samples , rock sample and food samples prior to their determination by ICP-OES. The recoveries for the addition of different amounts of metal ions to the samples were quantitative (˃95.0%) indicating the accuracy and applicability of the procedure.