الفهرس 
Chapter OneOnly 14 pages are availabe for public view
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Abstract
This thesis consists of two main chapters:
Chapter One: Published papers.
This chapter represents the two published papers as follows:
Paper (I):
Title: Microwave-enforced sorption of heavy metals from aqueous solutions on the surface of magnetic iron oxide-functionalized-3-aminopropyltriethoxysilane.
Authors: Mohamed E. Mahmoud, Mohamed F. Amira, Amal A. Zaghloul, Ghada A.A. Ibrahim.
Journal: Chemical Engineering Journal 293 (2016) 200–206.
Paper (II):
Title: High performance microwave-enforced solid phase extraction of heavy metals from aqueous solutions using magnetic iron oxide nanoparticles protected-nanosilica
Authors: Mohamed E. Mahmoud, Mohamed F. Amira, Amal A. Zaghloul, Ghada A.A. Ibrahim.
Journal: Separation and Purification Technology 163 (2016) 169–172.
Chapter Two: Unpublished results.
This chapter represents a general introduction about nanomaterials especially magnetic nonoparticles. Definition, functionalization, preparation methods and applications in water treatment were described. The magnetic nanoparticles especially magnetite can act as a good sorbents for effective and selective removal of heavy metal ions.
This chapter includes two main parts:
Part (I): Adsorptive removal of heavy metals from water by chemically modified
magnetic nanoparticles with folic acid.
Part (I) represents the abstract, experimental, results and discussion for removal of heavy metal ions viz. Pb(II), Cu(II), Cd(II) and Hg(II) by newly synthesized magnetic nanosorbents functionalized by folic acid, [Nano-Fe3O4-SiO2-FA] and [Nano-Fe3O4-SiO2-NH2-FA] sorbents using a microwave-assisted technique. The sorption processes were studied and optimized in the presence of different controlling parameters such as pH, contact time, sorbent dosage, initial metal ion concentrations and interfering metal ions by the batch equilibrium technique. The newly synthesized magnetic nanosorbents were characterized by scanning electron microscopy (SEM), high resolution transmission electron microscope (HR-TEM), X-ray diffraction (XRD), Fourier transform-infrared (FT-IR), thermal gravimetric analysis (TGA) and determination of surface area. The sorption isotherms of the metal ions by these nanosorbents have been also investigated by using the most widely used models, Langmuir and Freundlich isotherms. The mechanism of the sorption processes has been elucidated from the kinetic studies and we found that the pseudo-second-order kinetics is the correct model to describe the mechanism of adsorptive removal of Pb(II), Cu(II), Cd(II) and Hg(II) using [Nano-Fe3O4-SiO2-FA] and [Nano-Fe3O4-SiO2-NH2-FA] sorbents. The potential applications of these magnetic nanosorbents for heavy metal removal from real water samples (drinking tap water, waste water and sea water) have been studied.
Part (II): Surface modification of magnetic iron oxide nanoparticles-protected-
nanosilica by nicotinic acid as an efficient sorbent for removal of heavy
metals.
This part demonstrates the functioalization of [Nano-Fe3O4-SiO2] sorbent by nicotinic acid to produce [Nano-Fe3O4-SiO2-NA] sorbent by using a high performance microwave-assisted technique. The synthesized nonosorbent was characterized by scanning electron microscopy (SEM) and high resolution transmission electron microscope (HR-TEM), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) and determination of surface area. The incorporated selectivity and efficiency of the synthesized nanosorbent were examined for the removal of some heavy metal ions such as Pb(II), Cu(II), Cd(II) and Hg(II) from their matrices by the batch equilibrium technique at different values of pH, contact time, sorbent dosage, initial metal ion concentrations and interfering ions. The sorption processes of Pb(II), Cu(II), Cb(II) and Hg(II) from liquid solutions using [Nano-Fe3O4-SiO2-NA] sorbent were investigated by the pseudo first-order and the pseudo-second-order kinetic models to estimate the mechanism of sorption processes and the rate constant of the controlling step. We found that the pseudo-second-order kinetics is the correct model to describe the mechanism of adsorptive removal of these metal ions using [Nano-Fe3O4-SiO2-NA] sorbent. The sorption isotherms of these metal ions by the magnetic nanosorbent have been also investigated and it was noted that the sorption process of Pb(II), Cd(II), Cu(II) and Hg(II) by using [Nano-Fe3O4-SiO2-NA] sorbent are well described and more fitted to Langmuir isotherm rather than Freundlich isotherm. The potential application of the magnetic nanosorbent as an efficient adsorbent for the removal of Pb(II), Cu(II), Cd(II) and Hg(II) from drinking tap water, wastewater and sea water samples were accomplished using the batch equilibrium technique.