الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present thesis entitled “Removal of Some Toxic Elements from Underground Water” contains (73) pages, (112) References, (25) Tables and (29) Figures, and comprises of four chapters:
Chapter I is concerned with pollution, heavy metals and their hazardous effect, common techniques for removal of heavy metals and the previous studies made on the removal of Al3+, As3+ and SO42- ions by using adsorption technique.
Chapter II contained the experimental part for using marine fouling and sawdust as adsorbents for the removal of Al3+, As3+ and SO42- ions from aqueous solutions through batch adsorption process. Adsorbent was purified and characterized using FT-IR analysis to identify the surface functional groups of adsorbents.
Chapter III collected and discussed the obtained results. Removal efficiency of Al3+, As3+ and SO42- ions was investigated under various conditions, different concentrations of metal ion, amount of adsorbent, pH, adsorbent size and contact time at 300 rpm at room temperature (25°C).
The metal ions adsorption was highly pH-dependent. The percentage of removal of metal ions (Al3+and As3+) increases with increasing pH, where the maximum removal percentage of Al3+was 97% at (pH=5) and 90% at (pH=8) for As3+ions for marine fouling and sawdust. Maximum removal of SO42- ion was achieved at pH 3 with 100% for the two adsorbents.
The adsorption rate was very rapid during the first 20 min of adsorption and the percentage of removal of metal ions increased with increasing time until it reaches equilibrium. The percentage metal ions removal approached equilibrium within 30 min for Al+3 ions, 60 min for both As+3 and SO42- ions.
The adsorption increases with increasing the adsorbent doses and decrease of adsorbent size but the adsorption decrease with increasing the initial metal ion concentration.
The kinetic data were followed, the pseudo-second-order reaction model as it has high correlation coefficient R2. Pseudo-second-order kinetic model implies that the predominant process is chemisorption, which involves a sharing of electrons between the adsorbate and the surface of the adsorbent.
Langmuir isotherm fits the data. The monolayer adsorption capacities (qmax) for Al3+, As3+ and SO42- was 28.81, 23.58 and 34.48 mg/g, respectively for marine fouling and 28.65, 23.58 ,34.96 mg/g, respectively for sawdust. The higher value of R2 for Langmuir isotherm as compared to Freundlich isotherm indicated a better applicability of this model. This suggested that the adsorption of the metal ions occurs on a homogeneous surface by monolayer adsorption.
Chapter IV applying the treatment method used for removing Al3+ , As3+ and SO42- ions from synthetic water, underground water sample was collected from El-Meridian Hotel located in El-Haram, Giza, Egypt. Various dosages of the adsorbent in the range of (0.1-1 g) were added to a series of flasks each of them consisted of 50 mL of water sample and shacked at room temperature (25 °C) at 500 rpm for 60 min at pH 7. Good results were obtained as following: The removal percentage of Al3+ , As3+ and SO42- ions were 100%, 100%, 14% respectively with using 0.3 gm of adsorbents.