الفهرس 
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Abstract
The objective of this work is to utilize one of the natural waste plants, water hyacinth for oil spill cleanup. Water hyacinth is a free-floating perennial aquatic plant (or hydrophyte) represents large problem in the Egyptian water. It can be round in large water areas such as seas, wetlands, ponds. and lakes. With broad. thick, glossy. and ovate leaves. water hyacinth may rise above the surface ofthe water as much as I meter in height. This study aims to achieve two positive effects with regards to the environmental safety management. First, consumption this harmful waste plant as adsorbent materials to be utilized in oil spill adsorption process that can get rid of its spread over the water areas, which causes substantial problems. On the other hand, oil spill on water surfaces is considered a great environmental problem and there is an increasing interest in limiting the spread of such liquid hydrocarbons in the environment, especially marine areas. Accordingly. the utilization of water hyacinth as adsorbent materials for oil spill decontamination participates in solving the oil pollution problems in water. Experiments were carried out in a gradual pattern. First, the experiments were applied to the raw water hyacinth: the plant was separated into two segments. raw shoots and roots. in order to stud: their different oil sorption capacity and water pickup under simulated field conditions. Then chemical modification of these two different water hyacinth segments was carried out using alkali and acidic treatment. in order to improve their active surface area and induce a new exchangeable (II”) and (OH’) ions. Sorption capacity of the different chemical modified water hyacinth samples was measured to indicate the gradual noticeable improving in the oil adsorption bchav ior resulted from both acidic and alkaline treatment. Finally. carbonization process was done to improve the hydrophobic and oleophilic properties of the water hyacinth. Carbonization process was accomplished by using the chemical activation method using two different chemical compounds. II,PO~ and ZnCL~ as activating agents. prior to carbonization. Oil sorption capacity of the different prepared carbonized water hyacinth was measured and the most efficient prepared activated carbon which provides the highest oil sorption capacity and the 1011 est water pickup was selected for studying the factors affecting the oil sorption process. It is found that the most efficient prepared sorbent material driven from water hyacinth is the activated carbon prepared by the chemical activation of the alkaline modified water hyacinth roots with heating at 60° C by adding the zinc chloride (ZnCL2) as an activating agent. The physical and chemical characteristics of both two different raw water hyacinth segments. in contrast to the most efficient prepared sorbent material were investigated using four different techniques: X-ray diffraction (XRD), scanning electron microscopic (SEM), infrared br>spectroscopy (lR). and thermal gravimetric analysis (TGA). in order to show the inner and the outer surface and the cross section area of the sorbent material, as well as to investigate the thermal degradation profile of the used sorbent materials. It is important to make a comparison between the properties of the raw water hyacinth and the most efficient prepared activated carbon in order to illustrate the effect of carbonization process on the water hyacinth modification that improving its internal structure resulting in increasing the oil sorption capacity. Different factors were varied to study their effect on the oil sorption capacity. including sorption time. sorbent weight (the sorbent dosage). oil film thickness (the initial oil concentration). agitation speed. and sorption temperature. It is found that the best conditions are recorded after 60 min sorption time using 109 from the prepared sorbent material at initial oil film thickness of which represents initial oil concentration of 6.98 gl L. using agitation speed of 105 rpm. br>Concerning the sorption temperature effect. the sorption temperature was increased as the percentage oil removal and the amount of adsorbed oil increase. indicating that the process is endotherm ic. The different equilibrium and adsorption kinetics data for oil spill cleanup usmg the most efficient prepared sorbent material were theoretically modeled. Adsorption isotherm study was carried on lour isotherm models: the Langmuir. Freundlich. Temkin. and Dubinin-Radushkevich D-R) isotherm models. The applicability or the isotherm equation to the adsorption study done was compared by judging the correlation coefficient R2. It is found that the Freundlich model yielded the highest R~ value (0.9996). and this showed that the oil sorption on the prepared activated carbon was best described b) this model. which suggested that some heterogeneity on the surfaces or pores or the prepared activated carbon played a role in the oil sorption. On the other hand. four kinetic models namely pseudo first-order. pseudo second-order. Elovich. and intraparticle diffusion kinetic models were selected in this study to describe the sorption process. Till? pseudo second-order model) ielded the highest R2 value (0.9933). and this showed that the results can he well represented b) this model, which reveals that the main oil adsorption mechanism is probably chemisorption reaction.