الفهرس 
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Abstract
The thesis entitled ”Determination and Removal of Some Dyes by using Composite Materials” comprises four main Chapters:
The first chapter contains a literature survey on pollution problems in general industries and the methods used for removal of this pollutions. Also a literature survey on adsorption mechanism and the factors influencing the adsorption processes. Also the chapter contains the importance and applications of acid red 57 and acid yellow 99 dyes.
The second Chapter includes the experimental techniques used for preparation of Polyacrylonitrile/activated carbon composite (PAN/AC) and solutions preparation, also the analytical techniques used for the study were described in this Chapter.
Chapter 3 study the adsorption of acid red 57 onto (PAN/AC) composite, the adsorption capacity of acid red 57 was also examined using the adsorption isotherm techniques. It was found that the (PAN/AC) composite is an effective adsorbent for the removal of AR57 from aqueous solutions and polluted water. The highly adsorption capacity of AR57 onto (PAN/AC) composite was in highly acidic solution (pH 1) and this is due to the strong electrostatic interactions between the adsorption sites and the dye anion. Based on these results, for the application of Langmuir and Freundlich equations, the experimental results showed that the Freundlich model was the best. The highest value of n at equilibrium was (1.121) suggested that the adsorption was physical.
The kinetic data tends to fit very well in the pseudo-second order kinetic model with high correlation coefficients. The ΔGo values were negative, therefore the adsorption was spontaneous in nature. The negative value of ΔHo reveals that the adsorption process was exothermic in nature and a physical adsorption. The positive value of ΔSo implies that the increment of an orderliness between the adsorbate and the adsorbent molecules. SEM images shows well defined and characterized morphological images that are evident for the effective adsorption of AR57 molecules on the cavities and pores of the (PAC/AC) composite. Desorption studies were conducted and the results showed that (PAN/AC) composite can be used in adsorption of acid dyes several times by regeneration process by using sodium hydroxide solution at pH around 12.
Chapter 4 describes the removal of acid yellow 99 from aqueous solutions by the adsorption onto (PAN/AC) composite. The removal reached 99.8% of AY99 dye at 25 oC. Adsorption of the acid yellow 99 was highly pH-dependent. Also the adsorption of the acid yellow 99 decreases as the initial acid dye concentration increases. Temperature has low effect on the adsorption of acid dye onto the surface of (PAN/AC) composite. The adsorption of acid dyes increases as the composite dosage increases.