الفهرس 
Chapter One, Introduction & Literature SurveyOnly 14 pages are availabe for public view
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Abstract
The objective of the study was to synthesize and characterize nano montmorillonite / chitosan composites and their environmental applications. This study consists of three main chapters; the first chapter includes a small survey about water pollution, water treatment methods focusing on adsorption using polymer nanocomposites as a useful technique applied for removal of dyes or heavy metal ions from water systems, the application of chitosan/clay and chitosan/montmorillonite nanocomposites as adsorbents for dyes and heavy metal ions removal from aqueous solutions. Furthermore, optimization of the removal process applying response surface methodology using Central Composite Design (CCD) and Box–Behnken Design (BBD). Chapter two includes the materials used in the study and the experimental techniques. This chapter also includes removal measurements including effect of initial pH, adsorbent dosage, kinetics studies, adsorption isotherms, thermodynamics, and also, the study of removal percentage of Fe(III) ions and the two studied dyes (reactive blue 50 and mordant brown 15) onto one of the prepared nanocomposites employing 5-level CCD, and 3-level BBD, respectively, with four factors. The third chapter presents the results obtained from the study and discusses these results in six parts. The first part covered the characterizations of the prepared sorbents :IR confirmed the proposed structure of the prepared sorbents in addition to the attachment of each adsorbate to the functional groups of the prepared nanocomposites proposing the mechanism of adsorption of each adsorbate onto the prepared nanocomposites. Elemental analysis, which confirmed (C, H, N) percent in melamine modified polymer nanocomposites. TGA analysis showed the stability of the prepared nanocomposites. SEM pictures show the difference between morphologies before and after modification with epichlorohydrin/melamine as well as before and after adsorption of studied adsorbates. TEM pictures deduce that all the prepared composites are nanocomposite materials. Part 2 and Part 3: covered the optimization of conditions suitable for removal of reactive blue 50 (RB50) dye as well as mordant brown 15 (MB15) dye, respectively, from aqueous solutions using batch technique. Results obtained indicated the following: The optimum pH values for the maximum sorption capacity of RB50 and MB15 dyes molecules are at pH= 2 and 8, respectively. The effect of adsorbent amount on the removal percentage of both dyes has been studied. 0.02 g has been chosen for the next experiments. The equilibrium studies showed that the Langmuir isotherm shows a better fit to RB50 and MB15 dyes adsorption than Freundlich or Temkin. The obtained data comply with Langmuir type isotherm better, implying monolayer adsorption reaction on the surface of prepared adsorbents. The effect of temperature on the adsorption capacity of RB50 dye was studied and the thermodynamic parameters were calculated.The little change in the removal percentages of each dye was noticed when the nanocomposites were utilized three times leads to the possibility of reusing the prepared adsorbents for three sorption / desorption cycles. Part 4: covered the optimization of conditions suitable for removal of Fe(III) ions, RB50 dye, and MB15 dye onto one sample of melamine grafted nanocomposite with lowest MMT wt% from aqueous solutions using batch technique applying response surface methodology (RSM). Results obtained indicated the followings; for Fe(III) adsorption;Optimization was developed by CCD, showing the optimum values as follows: initial solution pH of 3, adsorbent dosage of 0.017 g, initial Fe(III) concentration of 120 mg L-1, and temperature 50 ̊C. Kinetic studies showed that the rate of Fe(III) removal followed pseudo-second-order kinetics. The isotherm models were applied and the equilibrium data were best described by the Freundlich model. Thermodynamic study showed that the adsorption of Fe(III) was spontaneous, endothermic and chemical in nature. The adsorbent used was best regenerated in 1 mole L-1 HCl solution and it could be successfully reused up to 3 cycles Part 5: covered the proposed mechanism of adsorption of each adsorbate on the prepared nanocomposites.Part 6: covered the application of the prepared adsorbents involving antimicrobial activity besides application to real water samples.