الفهرس 
Introductionيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
The growing need for the development of new methods in chemical technology represents a major challenge facing mineral, metallurgical and material processing industries in recent years. Water pollution is nowadays a matter of deep apprehension and as far as the toxic dyes are concerned, it is known that elevated concentrations of them are detrimental for aquatic life and through the food chain, are toxic for mankind. Therefore, intense scientific research is being directed towards the implementation of novel approaches dealing with the efficient removal of toxic dyes from wastewaters. Adsorption is considered an important treatment technology for this problem and several novel adsorbents and processes continuously appear in the scientific literature. Accordingly, this work is devoted to studying the different factors controlling the separation of crystal violet (CV) and Congo red (CR) dyes from aqueous media. The adsorption technique was the best among the well-known separation method because of its simplicity, saving time, accuracy alongside its inexpensive chemicals and equipment. Moreover, this investigation aims to establish the use of chemically treated olive pomace as a bio-sorbent. This thesis comprises three main chapters: Chapter I (Introduction and Literature Review) This chapter includes a general introduction to the different methods of separation with a focus on the method of adsorption. Moreover, it gives a literature survey, taking into consideration the recently reported papers, about the separation and recovery of crystal violet (CV) and Congo red (CR) dyes by different adsorbents. Chapter II (Experimental). This chapter outlines the equipment, reagents, and materials used in this investigation. Moreover, the general procedures used for the separation and recovery of CV and CR dyes by batch adsorption technique and the recommended parameters have also been described. Chapter III (Results and Discussion) This chapter is divided into three main parts: 1. characterization of prepared adsorbents. 2.Separation and recovery of CV dye using SHMP-OP, and PA-OP adsorbents. 3. Separation and recovery of CR dye using SHMP-OP, and PA-OP adsorbents. In the first part: The characterization of the adsorbents prepared from olive pomace was studied by infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), pH at a zero-point charge, and energy-dispersed X-ray analysis (EDX).In the second part: The removal of CV toxic dye from aqueous solutions was investigated by batch adsorption method using two different adsorbents (olive pomace treated with sodium hexametaphosphate, and olive pomace treated with phosphoric acid) as eco-friendly, low-cost, and effective bio-sorbents. The main parameters (i.e. initial solution pH, adsorbent and dye concentrations, contact time, temperature, and presence of foreign ions) that influence the adsorption process were examined. Also, some relations were studied such as kinetics, isotherm, and thermodynamic studies which showed that the adsorption of CV dye was endothermic, chemically in nature, and obey the second-order kinetic model. Moreover, the data showed that about 100% of the dye was removed at pH 7 and room temperature (25±2oC). Also, the adsorptive removal process was free from interference from the foreign ions investigated. Additionally, the adsorptive removal procedure was successfully applied to recover CV dye, spiked to some natural water samples, quantitatively under the recommended conditions. Moreover, the mechanism of adsorption is suggested. In the third part: The removal of CR toxic dye from aqueous solutions was investigated by batch adsorption method using two different adsorbents (olive pomace treated with sodium hexametaphosphate, and olive pomace treated with phosphoric acid) as eco-friendly, low-cost, and effective bio-sorbents. The main parameters (i.e. initial solution pH, adsorbent and dye concentrations, contact time, temperature, and presence of foreign ions) that influence the adsorption process were examined. Also, some relations were studied such as kinetics, isotherm, and thermodynamic studies which showed that the adsorption of CR dye investigated was endothermic, chemically in nature, and obey second-order kinetic model. Moreover, the data showed that about 100% of the dye was removed at pH 4 and room temperature (25±2oC). Also, the adsorptive removal process was free from interference from the foreign ions investigated. Additionally, the adsorptive removal procedure was successfully applied to recover CR dye, spiked to some natural water samples, quantitatively under the recommended conditions. Moreover, the mechanism of adsorption is suggested. Conclusions This study presents and clarifies the role of adsorption for the removal of the toxic organic dyes of CV and CR from aqueous solutions using (SHMP-OP and PA-OP) as good adsorbents with an efficiency of about 100%. Finally, the adsorptive removal procedure was succeeded in the recovery of the analytes from some natural water samples. Furthermore, an adsorption mechanism was suggested.