الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Summary and conclusions
The thesis aims to prepare zero valence iron and cobalt nanoparticles from different counter ions and then Preparation of zero valence iron and cobalt impregnated with silica and zeolite nanoparticles and the prepared nanoparticles were investigated by using different instrumentals. The prepared nanoparticles were used as adsorbents for the removal of alizarin red dye from water and also were used in electrical and magnetic applications. This thesis consists of three main chapters:
Chapter 1: Introduction
This chapter includes a brief introduction about water pollution, sources of Pollution and its harms on living things, as well as the different methods used to purify polluted water. It also includes the definition of nanomaterials and the different methods used in their preparation, as well as the different applications of nanomaterials. This chapter also contains literature survey on pervious work for nano zero valent metals and their nanocomposites. Also, it contains the applications of the nano zero valent particles in various fields such as water treatment, electrical and magnetic.
Chapter 2: Experimental
This chapter contains the practical part of this thesis. It involves complete description of the chemicals and reagents were used in the synthesis of nano zero valent iron and cobalt and then compounds prepared from impregnation with silica and zeolite. This chapter includes the description of the instrumental tools such as XRD, HR-TEM, FE-SEM, BET and UV-Vis spectrophotometer which used for the study of the synthesized nanoparticles. It also contains the batch method which used the removal of alizarin red dye from water using the fabricated nanoparticles as adsorbents. It also includes the explanation for the various factors influencing the removal efficiency. Also, it contains electrical and magnetic studies.
Chapter 3: Results and discussion
This chapter contains the discussion and results of the extracted data. It can be divided into four main parts.
The first part
The first part describes the characterization of the obtained nano zero valent metals and their compounds by different tools such as powder X-ray (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET and UV-Vis spectrophotometer. The previous results showed that the preparation of nano zero valent iron and cobalt were in the nanometer range. The crystallite size were determined using x-ray powder diffraction and was 7.51, 5.72, 8.22 and 9.54 nm for the FC, FN, CC and CN samples, respectively. The transmission electron microscopy showed the regular and irregular spherical shape which appeared as compact with each other in the form of network agglomeration for FC and the average particle size found to be 50 nm. Also, the transmission electron microscopy showed crystalline spherical shape with agglomeration for CC and CN. The average particle sizes are in the range of 11.52-22.35 nm. Also, XRD results showed that obtained nano zero valent iron and cobalt impregnated with zeolite in the nanometer range. The determined crystallite sizes using x-ray powder diffraction were found to be 4.51, 3.23, 5.11 and 6.22 nm for the FCZ, FNZ, CCZ and CNZ samples, respectively. The electron transmission microscopy for FCZ showed the regular and irregular spherical shape which appeared as compact with each other in the form of network agglomeration. The determined average particle sizes from TEM image are found to be 10 nm. XRD results showed that obtained nano zero valent iron and cobalt impregnated with silica in the nanometer range. The determined crystallite sizes using x-ray powder diffraction were found to be 4.11, 3.34, 5.23 and 6.31nm for the FCS800, FNS800, CCS800 and CNS800 samples, respectively. The electron transmission microscopy for FCS800 showed particles like spherical shapes and the average particle sizes are about 31.7 nm. Also, the electron transmission microscopy for CCS800 showed the crystalline spherical shape with agglomeration and the average particle sizes are about 19.8 nm. from BET measurements, the specific surface area (m2/gm) for (CCZ, CCS 800, FCZ, FC, CC and FCS800) nanoparticles were found to be 18.96, 17.73, 21.03, 10.3, 6.84 and 5.97, respectively.
The second part
The second part includes the adsorption data for the removal of alizarin red dye using the all fabricated nano zero valent particles. This part includes the results and discussion of the factors affecting the removal of the dye under study from aqueous solutions such as pH, contact time, initial dye concentration, adsorbent dose, ionic strength and temperature. The optimum conditions for the adsorption process were reached and the results were as follows:
1. The optimum pH for the adsorption of alizarin red dye was found to be 2 for FNZ, FCS800 and FNS800, 3 for FC, FN and FCZ, 5 for CNS800, 9 for CC, CN, CCZ and CNZ and 10 for CCS800.
2. The contact times for the adsorption of alizarin red dye using FC, FN, CC, CN, FCZ, FNZ, CCZ, CNZ, FCS800, FNS800, CCS800 and CNS800 samples were found to be 180, 120, 90, 60, 75, 60, 30, 60, 50, 40, 60 and 30 min, respectively.
3. The dye removal decreased with increasing the amount of NaCl using the all synthesized nano zero valent particles.
4. The dye removal increased with raising the temperature for all the synthesized materials.
5. The adsorption data followed well the Langmuir isotherm model for all the prepared nanomaterials. The adsorption of the alizarin red dye fitted the pseudo second order model for all samples for the separation of the alizarin red dye over nano-adsorbents.
6. The adsorption of alizarin red dye showed spontaneous, physiorption and endothermic process using all the prepared samples.
7. The adsorption capacities of FC, FN, CC, CN, FCZ, FNZ, CCZ, CNZ, FCS800, FNS800, CCS800 and CNS800 samples for removal alizarin red dye were found to be 139.6, 99.4, 119.9, 92.2, 141.9, 142.7, 140.6, 146.5, 143.9, 146.8, 135.2 and 126.8 mg/g, respectively.
The third part
Study of the electrical conductivity for the prepared samples showed that, metals (FC and CC) have the highest value of conductivity which characterizing superionic of the present compounds. The dielectric parameters εˋand εˋˋ showed that their values are higher in nano zero valent pure metals than compounds resulted from impregnation with zeolite and silica. In addition, the effect of asymmetric electrodes on conduction and dielectric properties of superionic pressed powder solid electrolyte give high values of dielectric constant εˋ which show that nano zero valent particles forms a blocking and it is a good electrode material for solid state battery applications.
The forth part.
from the change in the value Δm with respect to the change in the square value of the field intensity H2 for the studied materials, it appeared that all these relations are straight lines. According to the above obtained straight lines, the magnetic susceptibility values of these samples were then calculated. While substances with a negative susceptibility are diamagnetic and substances with a positive susceptibility paramagnetic and from the positive values of magnetic susceptibility, it reveals that all samples are paramagnetic materials and the magnetic susceptibility in impregnation with silica are the highest values than others.