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Abstract ”Summary : This thesis comprises three main chapters: I- Chapter One (Introduction) It includes the fundamental complications with dye waste water, several ways for treating it, dyeing process, and the importance of using adsorption as a useful technique used for separation and preconcentration of dyes prior to their determination. Also includes the importance of modifications of the cotton, some of these advantages include; 1- Enhanced dye uptake 2- Improved color fastness 3- Better fabric handling and appearance and 4- Environmental impact reduction. The literature survey covering the general characteristics of the polymeric organic cellulose, their physical and chemical properties, advantage gained by oxidation and modification with different cationizing agents. Different methods used for the modification of the cellulose were reported. It is also including the use of these modified cellulose, as extractors for adsorption of anionic dyes. General view on chitosan compound and it’s applications in textile sector. Also, cationization of chitosan and it’s importance.II- Chapter Two (Experimental). This chapter describes the processing and details of analytical methods used throughout the thesis and include the following items • Materials and preparation of solutions (i.e dye solutions). • Equipment: (IR, X- ray diffraction, XPS, pH meter, scan electron microscopy). • Synthesis of modified cellulose: 1-Preparation of (Gr(T)-MC). 2- Preparation of (TAG-MC). 3- Preparation of chitosan graft-copoly(acrylonitrile) (CS-g-PAN). 4- Preparation of cationized CS-g-AN / GR(T). 5- Preparation of grafted cationized chitosan ([2-(Methacryloyloxy)ethyl] trimethylammonium chloride) (CS-g-MOTAC) • Methodology: Batch method: (effect of pH, effect of temperature, Kinetics of the dyes sorption and test for the reusability of modified cellulose). Applications of the proposed method for the separation, preconcentration and determination of dyes from dye solutions. III- Chapter Three (Results and Discussion): It divided into three main parts: Part I: Covered the characterization studies which applied for the crosslinked cellulose fibers using FTIR, Scan Electron Microscopy (SEM), Zeta Potential, X-Ray Diffraction (XRD), Elemental Analysis, and Energy dispersive X-ray spectroscopy (EDX). The presence of cationizing agents bound to the cellulose was evidence through the following: 1- Elemental analysis: indicated that, the amount of (N) atom found in the modified cellulose taken as evidence for the modification of the cellulosic cotton fiber. 2- Scan electron microscope: indicated that, the long and narrow streps observed on the oxidized cotton surface could be attributed to the partial corrosion of the fiber upon periodate treatment and relatively rough and porous surface taken as evidence for the modification and cationization. 3- X- ray diffraction: the crystalline pattern of the fibers exhibited an obvious decrease, which could be explained as a result of hydrogen bond breaking between the cellulose hydroxyl groups and subsequent creation of more amorphous region. The natural cotton and the cotton that has cationized chitosan fibers have crystallinity indices of 72.20 and 70.91%, respectively. These findings show that after cellulose fibers are modified, the ordered structure of crystalline cellulose is not substantially changed. 4- EDX: Because the X-rays are specific in their energy for each atom, they can reveal crucial chemical details about the sample that contains metal. from the obtained results, the newly peak of nitrogen with principal peaks for C and O are shown for cotton with cationized chitosan (Cationized CS-Cotton) with compared to native cotton. 5- IR spectra of oxidized cotton, Gr(T)-MC and TAG-MC compared with cellulose exhibited three addition new characteristic at 1750 which would be attributed to the C=O, 1680 cm-1 ,1725 cm-1, which could be attributed to the C=N peak; are taken as evidence for the modification of the cellulose. The unmodified chitosan’s spectrum revealed peaks at about 3500 cm−1 caused by N-H stretching vibrations. The chitosan grafted -co-acrylonitrile’s spectrum (Ch-g-PAN) presented an obvious peak at nearly 2251 cm-1, in accordance with the newly created cyano group stretching vibrations. Following the interaction with Girard T, the generated (Ch-g-PAN-GT) spectrum displays a novel peak at around 1775 cm-1, corresponding to the C=NH group. It was found that the intensity of cyano group was decreased, which can be taken as indication of the formation of (Ch-g-PAN-GT). Part II: Covered the optimization of conditions suitable for adsorption of dyes by cationized cellulose using batch method. Optimization studies; Concentrations of Monomer, initiator, Effect of temperature, Measurement of dye fixation rate and dyeing levelness, and fastness properties. Results obtained indicated the following: 1- The optimum pH for the maximum sorption capacity of studied dyes adsorbed by Gr(T)-MC lie within the range pH (3-4) for ECR dye, and pH (7) for SPADNS dye. 2- The optimum pH for the maximum sorption capacity of studied anionic dyes adsorbed by TAG-MC lie within the range (3-4) for ECR dye and pH (7) for SPADNS dye. 3- The optimum condition such as effect of monomer concentration, effect of initiator concentration, effect of reaction temperature(oC) and effect of reaction time (hr) were detected where the concentration of chitosan is 0.5g were applied for determination of Graft yield (%G) and Grafting efficiency (% GE). 4- The effect of the concentration of Chitosan on the cationization can be determined by studying the change of dye uptake by changing the concentration of chitosan. The aqueous dye solutions with certain concentrations and pH values were submerged in 0.01 g of adsorbent cationized chitosan, which was made in plastic bottles. 5- Measurement of dye levelness and dye fixing rate; A Data Color 650 spectrophotometer was used to measure the K/S value, which was 520 nm for ECR dye and 550 nm for SPADNS dye. This allowed for the determination of the dye’s color strength. 6- After the successful synthesis of quaternary ammonium salt derivatives of chitosan via quaternization of chitosan as a kind of cationic polyelectrolyte, is determination of the optimum conditions for maximum anionic dye uptake without using salts or alkali and in the neutral pH medium including chitosan concentration, initiator concentration, monomer concentration, effect of temperature, and effect of time. Part III: The proposed procedure was successfully for adsorption and removal of organic anionic dyes (ECR, SPADNS). By Utilizing Girard T and triaminoguanidine, we successfully cationized cellulosic fiber before applying it to anionic dyes (ECR and SPADNS). It was successfully possible to create the quaternary ammonium salt of chitosan by graft copolymerization with acrylonitrile and inlaying with quaternary ammonium salt Girard (T) reagent and crosslinking the cationized chitosan with a previous U.V irradiation of the raw cellulose sample. Successfully synthesis of quaternary ammonium salt of Chitosan by graft copolymerization with [(2-methacryloyloxy) ethyl] Trimethyl ammonium chloride by using Ammonium Persulphate, and crosslinking the cationized chitosan with a previous U.V irradiation of the raw cellulose sample using citric acid and sodium phosphate. To maximize anionic dye uptake to the cellulose fibers, cationized chitosan cross-linked cellulose fibers were created utilizing non-toxic techniques. In previously UV-irradiated cellulose fibers, citric acid was used as a cross-linker and NaH2PO4 as a catalyst. The work presented here was directed towards the preparation of cationized cellulose via its crosslinking with Triaminoguanidine or the quaternary ammonium Girard (T) or with the cationized chitosan itself. Graft copolymerization of chitosan (CS) with acrylonitrile (AN) was carried out by free radical graft copolymerization using ammonium persulfate (APS) as initiator and its inoculation by quaternary ammonium Girard (T) reagent to increase the density of the positive charge on CS then crosslinked with the previous U.V irradiation of the raw cellulose sample. In the end, we have achieved our goal of increasing the dye uptake and completing the dyeing process without using salt or alkali, and also water and energy waste have been reduced and there is no effluent.” |