الفهرس 
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Abstract
SUMMARY
Dyes have become one of the main sources of severe water pollution as a result of the rapid development of the textile industries. Dyes, especially those with good water solubility are difficult to be removed from their effluents due to their inert properties-anti-degradability by photos, oxidants and biological agents. Besides, their low amounts in the effluents always bring on high costs of treatment. The adsorption processes have been preferred to remove colors from waste effluents because of their low initial costs, simplicity of design and ease of operation. Recently, adsorption techniques using composite have been developed to absorb anionic and cationic dyes from aqueous solutions.
Thesis consists of three main chapters:
The first chapter is the introduction. It explains the water pollution and its sources. In addition, it contains a survey about most modern techniques used to remove dyes from wastewater. The types of different adsorbents are illustrated, showing the properties of good adsorbents for dyes removal. At the end of this chapter, a literature survey about the recent publications of adsorption Remazol Brilliant Blue R dye and uses of composites as adsorbent.
The second chapter is the materials and methods. This chapter mainly focuses on experimental reagents used for batch adsorption experiments and various characterization techniques for composites.
The third chapter is the results and discussion. It consists of two parts:
First Part:
Chitosan (natural polymer), glycidyl methacrylate (synthetic polymer) and magnetite are combined to produce novel magnetic macro-reticular hybrid synthetic–natural materials for the uptake of RBBR ions from aqueous media. The prepared sorbents was characterized via FTIR, SEM and EDX. These sorbents exhibited high adsorption capacity towards RBBR. The maximum monolayer adsorption capacities close to 0.153 and 0.174 mmol g−1 for MCGMA-I and MCGMA-II, respectively at approximately pH 2 and 25 oC. The nature of interaction between the dye anions and the sorbents was found to be dependent upon the acidity of the medium. The adsorption process carries out by anion exchange mechanism; however the adsorbent maintained a significant adsorption capacity at alkaline pH. The adsorption isotherms are well fitted by the Langmuir equation. Uptake kinetics is correctly fitted by the pseudo-second order rate equation. The thermodynamic parameters have been determined: the reaction is endothermic, spontaneous. The randomness of the system increases with RBBR adsorption. Even under drastic conditions of high ionic strength, the sorbent maintained its high sorption capacity. The adsorbents can be used successfully up to 4 times without significant loss of its original efficiency regenerated by 0.5 M NaOH. This means that the studied sorbent is a promising sorbent for the efficient removal of dyes from wastewater.
Second Part:
Magnetic chitosan was prepared by co-precipitation with polymeric Schiff’s base resulting from the reaction of thiourea with glutaraldehyde for the removal of Remazol Brilliant Blue R (RBBR) from aqueous solutions and characterized via FTIR, SEM and EDX. This sorbent exhibited high adsorption capacity towards RBBR. The maximum monolayer adsorption capacities are 0.441 mmol g−1 at pH 1.6 and 25 oC. The nature of interaction between the dye anions and the sorbents was found to be dependent upon the acidity of the medium. The adsorption process carries out by anion exchange mechanism; however the sorbent maintained a significant adsorption capacity at alkaline pH. The adsorption isotherms are well fitted by the Langmuir equation. Uptake kinetics is correctly fitted by the pseudo-second order rate equation. The thermodynamic parameters have been determined: the reaction is endothermic, spontaneous. The randomness of the system increases with RBBR adsorption. Even under drastic conditions of high ionic strength, the sorbent maintained its high sorption capacity. The RBBR anions can be efficiently desorbed from loaded sorbent with alkaline solution of 0.5 M NaOH and that the sorbent can be reused for a minimum of 4 sorption/desorption cycles with a limited loss in efficiency (less than 2.7 %) at the fourth sorption cycle. This means that the studied sorbent is a promising sorbent for the efficient removal of dyes from wastewater.
Finally, the results in this research confirmed that Magnetic-chitosan–glycidyl methacrylate macroreticular hybrid material (MCGMA-I and MCGMA-II) and Magnetic Polymerized Thiourea Cross Linked Chitosan (MPTC) were useful as low cost materials, readily available and suitable sorbents for the removal of Remazol Brilliant Blue R (RBBR)from aqueous solutions.