الفهرس 
Introduction (Literature SurvayOnly 14 pages are availabe for public view
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Abstract
The present thesis includes four major parts;
Part one:
This part contains the introduction of this thesis. Introduction includes the production/processing of chitosan, the biological and chemical properties of chitosan, modification of chitosan by different methods, biological activities of chitosan and Grafted Chitosan. In addition to, the synthesis and some applications of Polyacrylonitrile are present.Finally, application and synthesis of Chitosan polyacylonitrile, synthesis and application of Chitosan nano composites, synthesis and application of Chitosan Grafted Polyacrylonitrile Nanocomposites, synthesis and application of Chitosan /ZnO Nanocomposites, synthesis and application of Polyacrylonitrile /ZnO Nanocomposites.
Part two:
This part contains the aim of this work to Synthesis and characterization of chitosan-grafted polyacrylonitrile/ZnO was achieved and apple to remove iron from ground water.
Part three:
This part includes the discussion section represented in our publication. The main target of this thesis is Chitosan-g-polyacrylonitrile ZnO nano-composite, synthesis and characterization as new and good adsorbent for Iron from groundwater. The synthesized polymers by Oxidative chemical polymerization reaction were investigated for the Synthesis of Poly Acrylonitrile PAN, Preparation of Chitosan-Graft-PAN (Cs-g-PAN). APS was used as an oxidant and the polymerization reaction was completed under N2 atmosphere. This grafting copolymerization reaction was based reactive NH2 group present in chitosan. Finally Preparation of Chitosan-Graft-PAN/ZnO (CS-g-PAN/ZnO) and Poly Acrylonitrile/ZnO (PAN /ZnO) composites
The prepared polymeric structures were characterized by infrared, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, EDX, Transmission Electron Microscope (TEM), and BET analysis. Through this characterization, the synthesis of Cs-g-PAN, ZnO, PAN-ZnO, andCs-g-PAN/ZnO sample were proved.
IR spectroscopy demonstrated that the peak exhibits broad absorption bands at 3424 cm-1 due to the stretching mode of NH and OH groups. The typical peaks at 2928 and 2874 cm−1 are ascribed to aromatic and aliphatic C-H bond stretching vibration, the strong peaks at around 2242 cm-1 appeared in spectra assigned to the stretching absorption of –CN. And new broad absorption band at the range of 580–400 cm-1 was found in the FTIR spectra, which were ascribed to the vibration of the O-Zn-O groups.
The XRD patterns show that the synthesized polymeric structures are amorphous. from the data accompanied with XRD charts the crystallites size Cs-g-PAN, the diffract grams of pure chitosan sample shows the intense peak at 2θ= 17° is due to the crystal planes of PAN. The broadening of the peak at 24 is due to the amorphous nature of the polymer. Pure ZnO the characteristic peaks at 2θ = 31.87°, 34.55°, 36.35°, 47.59°, 56.66°, 62.89°, 66.40°, 67.89°, 69.17°, 72.59° and 77.00°. The same peaks appear in the structure of (PAN-ZnO, and Cs-g-PAN/ZnO). These results suggested the successful formation of crystalline zinc oxide on PAN-ZnO and Cs-g-PAN/ZnO composites.
SEM pictures showed agglomerated uniform spherical-shaped nanostructure with an average diameter of 150-170 nm for Cs-g-PAN, shape of granular ZnO nanoparticles with a diameter range of 10-15 nm. Clearly, the homogenous distributions of ZnO on the surface of lump fiber-like PAN, Cs-g-PAN/ZnO displays the incorporation of ZnO nanoparticles through its matrix.
EDX analysis for PAN-ZnO and Cs-g-PAN/ZnO composites display the main peaks of C, O, and Zn. The presence of a Zn peak in the EDX spectra confirms the successful loading and incorporation of ZnO on the surface of PAN and Cs-g-PAN.
TEM photographs evaluated to probe further into the size, morphology, and homogenous distribution of ZnO NPs on the surface of polymeric materials. Obviously, the homogenous distribution of the spherical and Hexagonal structure of ZnO on the surface of PAN and Cs-g-PAN.
The thermal stability of the obtained polymeric structures was checked by TGA, on set decomposition temperature at 285 °C which is higher than that of Cs-g-PAN (236 °C). Continuous decrease in weight till 350℃ with weight loss of 27% in Cs-g-PAN and 19% in Cs-g-PAN/ZnO due to degradation of chitosan73. Finally, at 850℃ the total weight loss for Cs-g-PAN and Cs-g-PAN/ZnO was ” ” ” " ~ " ” ” ”50% and 25%, respectively. So, Cs-g-PAN/ZnO displayed higher thermal stability than Cs-g-PAN due to the incorporation of ZnO into the Cs-g-PAN matrix.
BET reveals that the adsorptions on these surfaces are display type IV isotherm curve with H3 hysteresis loop. Type IV isotherm is an indication of the mesoporous nature of the prepared materials. he surface area decreased from 25.54 m2g−1 in Cs-g-PAN to 20.23 m2g−1 in Cs-g-PAN/ZnO, which assigned to the loading of Zn atoms into the bare Cs-g-PAN skeleton. The pore size and pore volume increment in the order ZnO<PAN-ZnO< Cs-g-PAN/ZnO is matched well with its adsorption capacity behavior.
Adsorption Studies for Cs-g-PAN, ZnO, PAN-ZnO and Cs-g-PAN/ZnO were introduced to the studying of their efficiency towards the removal of iron from ground water. All experiments were performed at pH = 7 and 25 0C. Using different dose (0.025 to 0.3 g for Cs-g-PAN) and 0.01 to 0.05 g of (ZnO, PAN-ZnO, and Cs-g-PAN/ZnO). The optimum adsorbent dose for Cs-g-PAN was 0.3 g, while for ZnO, PAN-ZnO and Cs-g-PAN/ZnO were 0.05 during 30 minutes of reaction. The Cs-g-PAN achieved 100% adsorption by using 0.3 gm.
Adsorption isotherms: we study Langmuir model, the Freundlich model, Temkin isotherm model are used to analyze the adsorption results. The comparison of the fitting parameters of the aforementioned isotherm models for the four investigated samples Cs-g-PAN, ZnO, PAN-ZnO and Cs-g-PAN/ZnO revealed that the Langmuir model fitted the adsorption data better than the Freundlich, and Temkin as indicated by the higher R2. The Langmuir model supposes monolayer adsorption of Fe (II), over the homogenous surface of the prepared catalysts.
Adsorption kinetics: from the obtained data. Two correlation coefficients R2 for the pseudo-first-order kinetic model and the pseudo-second-order kinetic model were calculated. Clearly, R2 > 0.99 for Pseudo-second-order kinetic model has shown a better correlation than R2< 0.99 for the Pseudo-first-order kinetic model for the adsorption of the Fe metal ions with the prepared catalysts.
We study the effect of interfering ions on the adsorption process. This indicates the great selectivity of Cs-g-PAN/ZnO for Fe(II) removal more than Mn(II) and suggested the great potential of Cs-g-PAN/ZnO for application on underground Fe(II) removal.
We study photocatalytic effect on the removal mechanism of Fe(II). This indicates the removal of Fe(II) increases under sunlight in comparison with the dark condition. For ZnO, PAN-ZnO, and Cs-g-PAN/ZnO.
Finally biodegradability study clearly, the presence of ZnO on Cs-g-PAN/ZnO surface has a small impact on its biodegradation due to its low concentration in the composites.