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Abstract It includes the importance of using solid phase extraction (SPE ) as a useful technique used for separation and preconcentration of trace metal ions prior to their determination .SPE is experienced with several major advantages over other liquid extraction tools , some of these advantages include ; 1-The fast , simple and direct application in very small sample amounts without any loss 2- No waste generation as practiced in the liquid extraction 3- Low risk of contaminations and 4- Time and cost saving . The literature survey covering the general characteristics of the Egg shell and Marble waste, their physical and chemical properties, the harmful effect of some metals under study Pb2+, Cd2+ and Cr3+ ions. It is also includes the use of these ES or PMW, as solid phase extractors for selective extraction , pre-concetration and selective separation of metal ions from aqueous media . II-Experimental This chapter describes the processing and details of analytical methods used throughout the thesis and include the following items Materials and preparation of solutions (i.e metal ions , buffers) Equipments (Atomic absorption spectrometr , IR, EDX, pH meter , scan electron microscopy) . Preparation of ES or PMW Methodology : Batch method: (effect of pH, effect of temperature, Kinetics of the metal ions sorption ) Applications of the proposed method for the separation , pre-concentration and determination of metal ions from different samples ( i.e., Tap and ground water samples ) III- Results and Discussion : It divided into three main parts : Part I : Covered the charactreisations of the ES or PMW. The presence of adsorbed metlal ions under study bound to the ES or PMW was evidence through the following: Scan electron microscope: indicated that, the long and narrow streps observed on the ES or PMW surface in addition to relatively rough and porous surface taken as evidence for the uptake metals under study EDX : , the EDX spectrum of ES or PMW before and after metal ions uptake obviously presents specific absorption peak. Furthermore, the appearance of different absorption peaks for different metals in the spectrum of the modified ES or PMW presented in may also gives an evidence for the uptake of different metals. IR spectra of ES or PMW after metal ion uptake with small shift in some absorption peaks can be taken as evidence for the metal ins uptake in ES or PMW Part II : Covered the optimization of conditions suitable for separation and preconcentration of some harmful metal ions from different matrices using batch method and using ES or PMW Results obtained indicated the following: The optimum pH for the maximum sorption capacity of all studied metal ions lie within the range (7-9) but we choose pH7 to avoid precipitation of metal ions under study The sorption capacity of ES or PMW, is lie within the range (20-40 mg g-1) for Cd (II), Cr (III), Pb (II) . Adsorptions of 20 mg/l pf Pb2+, Cd2+ and Cr3+ onto 0.1g of ES or PMW at 278, 283, 298, 313 and 333 K of different shaking were studied. It was found that, the sorption of metal ions increased by increasing the temperature which means that the adsorption process was endothermic The values of ΔHo of adsorption of Pb2+ or Cd2+ or Cr3+ onto ES or PMW sorbent were positive which means that the process was endothermic from the negative of ΔGo of adsorption process in the present of Pb2+ or Cd2+ or Cr3+ onto ES or PMW, indicate that the adsorption process was spontaneous. Part III: The proposed procedure was successfully for separation, Preconcentration and determination of harmful metal ions in different samples: 1-Tap water 2-Ground water. |