الفهرس 
CHAPTER IOnly 14 pages are availabe for public view
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Abstract
Nanocrystalline materials are showing great prospects in industry and technology. This is mainly because they have some unique properties which are not shown by the bulk crystalline materials. Nanomaterials represent almost the ultimate in increasing surface area.
Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1, significantly larger than any other material. These cylindrical carbon molecules have novel properties, making them potentially useful in many applications in nanotechnology, electronics, optics, and other fields of materials science.
Carbon nanotubes (CNTs) are relatively new adsorbents that can adsorb trace pollutants from wastewater. CNTs have been proven to possess great potential as superior adsorbents for removing heavy metals from waste water.
Carbon nanotubes (CNTs) were functionalized using mixture of concentrated nitric acid /sulfuric acid (3:1 by volume, respectively),the functionalized CNTs were used for adsorption of four heavy metals (Pb+2, Cu+2, Ni+2 and Cd+2) from waste water.
Carbon nanotubes (CNTs) could be adhered on glass sheets and used as adsorbent for Pb+2 ions from fish farms to avoid any harmful effect on fish life.
Throughout this work it was found that:
• Fe-Co/CaCO3 catalyst/support was successfully prepared by wet impregnation method and was characterized by XRD.
• The MWCNTs was synthesized by chemical vapor deposition (CVD) of acetylene on the catalyst surface at 600oC formed in homogeneous form with high density and high purity.
• The synthesized MWCNTs were purified by mixture of concentrated nitric acid /sulfuric acid (3:1) respectively, leading to formation of functional groups on its surface.
• The functionalized MWCNTs were characterized using FTIR, TEM, BET and TGA.
• FTIR spectra of functionalized MWCNTs confirmed the presence of several functional groups. These produced functional groups can provide numerous chemical sorption sites on MWCNTs surface.
• TEM micrographs of the oxidized MWCNTs showed well graphitized walls without any remarkable coverage of other materials also the effect of acid treatment was observed, the longed as prepared carbon nanotubes turned to smaller one since it was divided to many lengths to produce short carbon nanotubes with open ends.
• The BET method showed some physical properties, the specific surface area value of the acidified MWCNTs was very large. This large value supports high adsorption capability & increase the adsorption active sites