الفهرس 
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Abstract
Providing clean and healthy water to meet human needs is an important challenge in this century. The need for innovative methods to enable integrated water management cannot be exaggerated. Adsorption process possesses great potential in water and wastewater treatment to enhance treatment efficiency as well as to raise water supply through safe use of untraditional water sources. Here we tried to solve this problem by activation of the Egyptian bentonite clay which used in wastewater treatment to remove dyes and heavy metals.
This study is concerned with the activation of natural bentonite clay and the use of this activated bentonite clay in the treatment of wastewater from methylene blue dye as an example of organic pollutant and heavy metals (Pb2+, Cu2+ and Ni2+) as an example of inorganic pollutant.
The thesis is divided into four chapters:
1. Chapter one is the introduction and presented the problem of pollution from industrial wastewater which contains dyes and heavy metals. It also presented the adsorption process using clays as an effective technique. Finally, it presented basic notes about bentonite clay and its use in wastewater treatment from dyes and heavy metals.
2. The second chapter is the previous investigations literature & review and what has been done in the methods of bentonite activation and using the activated bentonite as a material to treat wastewater from dyes and heavy metals.
3. The third chapter is concerned with the tools, material & methods of the experiments used in this study to activate the natural bentonite clay. This chapter included:
• Crushing, grounding and purification of the natural Egyptian bentonite clay using 0.1 N acetic acid at room temperature to get rid of carbonates then passed through magnetic separation to decrease iron content.
• Characterization of natural and purified bentonite clay by X-ray fluorescence analysis, XRF (ZSX Primus IV, Rigaku), X-ray diffraction analysis, XRD (Panalytical X´PERT PRO), swelling test and cation exchange capacity (CEC).
• Activation of the purified bentonite clay was studied as follow:
I. Five samples (B1-B5) were activated by 1, 3. 5, 7 and 9 % HCl and another five samples (B6-B10) were activated by 1, 3, 5, 7 and 9 % H2SO4.
II. Another five samples (B11-B15) were activated by 1, 3, 5, 7 and 9 % Na2CO3 and five samples (B16-B20) were activated by 1, 3, 5, 7 and 9 % NaOH.
• The characteristics of all the activated bentonite samples were investigated using XRF (ZSX Primus IV, Rigaku), swelling test (ASTM- D5890) and Cation Exchange Capacity (CEC).
• 5% sodium carbonate activated sample (B13) was selected to study wastewater treatment because it has the best swelling and more cation exchange capacity.
• Methylene blue dye (as an example of organic pollutant), Pb2+, Cu2+ and Ni2+ (as an example of inorganic pollutant) were removed from wastewater by 5 % Na2CO3 activated bentonite sample (sample B13) by varying several parameters (pH, temperature, initial concentration, bentonite dose and time effect).
• Langmuir and Freundlich models were used to describe the equilibrium data.
4. The fourth chapter discusses the results that have been reached in the experiments. It included:
• Purification of the natural Egyptian bentonite clay using 0.1N acetic acid and magnetic separation which resulted in elimination of carbonates and reducing iron content and the results confirmed by XRF and XRD analysis.
• XRF, swelling test and Cation Exchange Capacity (CEC) results supported the choice of sample B13 (5% Na2CO3) as an adsorbent for methylene blue dye and heavy metals (lead, copper and nickel)
• Optimum results for methylene blue removal were pH 7, 1 g/L adsorbent dose, 40 minutes contact time, 200 mg/L initial dye concentration and 20 ºC temperature.
• The adsorption equilibrium obeys Langmuir equation with R2 = 0.999.
• Optimum results for heavy metals removal were pH 7, 1.25 g/L adsorbent dose, 60 minutes contact time, 10 mg/L initial metals concentration and 50 ºC temperature for lead, copper and nickel.
• The adsorption equilibrium obeys Langmuir equation with R2 = 0.998 for lead, R2 = 0.997 for copper and R2 =0.996 for nickel.
At the end, we can conclude that activated Egyptian bentonite clay can be used as excellent adsorbent because of its high swelling and cation exchange capacities. As well as it can be used as cost effective adsorbent in wastewater treatment plants to remove dyes and heavy metals.