الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
This chapter was mainly divided into three main parts. First part introduces an outline for the presence of Zircon mineral in Egypt and the extraction of zirconium form Egyptian zircon sand using solvent extraction technique, it also includes different theories used to explain solvent extraction and the previous work done on the extraction of zirconium using this method. The second part of this chapter mainly defines the nanomaterials, their synthesis techniques and their applications in different fields are presented. The third part includes the methods used for synthesis of graphene before and after adding nanoparticles and their applications for heterogeneous catalysis.
Chapter 2, the experimental:
The experimental part includes complete description of the materials, reagents and methods used for the extraction and stripping of zirconium from nitrate medium using TBP and Cyanex921. It is also includes synthesis of nanosized zirconium oxide using single stage microemulsion method and LVCC method. single stage microemulsion method was done by using three surfactants (CTAB, AOT and Oleylamine). This chapter also explains the doping of palladium nanoparticles on the prepared nanoparticles using microwave method and their application for low temperature carbon monoxide oxidation. This work was followed by mixing the prepared nanoparticles and palladium with graphene to show the effect of adding graphene on their catalytic activity for CO oxidation.
The prepared samples were mainly characterized using different techniques like: XRD, FT-IR, ICP, TEM, XPS, UV-Vis and Raman spectroscopy. These techniques were used to confirm the extraction of pure zirconium oxide and also the synthesis of zirconia and palladium nanoparticles.
Chapter 3, results and discussions:
This chapter is divided into four main parts. The first part of this chapter was consists of the extraction and separation of zirconium using Cyanex921 was studied with respect to various factors. These factors were the effect of Cyanex921 concentration, contact time, diluents used, phase ratio (O:A) v:v and HNO3 concentration. It was found that the optimum conditions for extraction of zirconium from the nitric medium were 6% Cyanex921 in kerosene and 10 minutes contact time at phase ratio (2:1). The obtained results also show that the extraction efficiency for Zr+4 at these optimum conditions was 99.6%. Additionally Decanol was chosen to be the best modifier for solving third phase problem.
The stripping or re-extraction of zirconium from loaded Cyanex921 was studied with respect to various factors. These factors were the type of stripping agent, the effect of stripping agent concentration, contact time and phase ratio (A:O) v:v. It was found that the optimum conditions for 94.1% re-extraction efficiency of zirconium from the pregnant solution was H2SO4 with concentration 4M, also the contact time was found to be 10 minutes at phase ratio (A:O) (1:1).
The second part includes the extraction and separation method of zirconium from nitrate medium using TBP. It was found that the optimum conditions for the extraction of zirconium using TBP is O:A phase ratio 1:1, TBP Concentration is 6%, Contact time is 5minutes, HNO3 concentration is concentrated acid and the diluent is kerosene and the extraction efficiency using these conditions was found to be 88.4%. So that Cyanex921 is better than TBP for the extraction of zirconium in nitrate medium.
For the stripping of zirconium from loaded TBP, it was found that the optimum conditions for the stripping of zirconium as follow: stripping agent: 4M HCl, A:O phase ratio is 2:1and contact time is 20 minutes. The obtained stripping efficiency was found to be 94.13%. It is clear that the stripping efficiency for both TBP and Cyanex921 is the same but the time needed for the stripping of zirconium from loaded TBP and also the amount of stripping agent used for the stripping process is higher incase of TBP than Cyanex921, so that the stripping of zirconium from loaded cyanex921 is easier than stripping of it from loaded TBP.
The chemical analysis of TBP and Cyanex921 ZrO2 products shows that the grain size of Cyanex921-ZrO2 (15-17nm) product is smaller than that of TBP-ZrO2 product (20-25nm). It was found that the best catalytic activity of these two products after doping with 5% Pd was Cyanex921 ZrO2-5% Pd, thus it makes complete oxidation for CO at 151 °C. It is clear that Cyanex921 was better than TBP for the extraction of zirconium from nitrate medium and its product with palladium gave higher catalytic activity than TBP product.
The third part explains the synthesis of zirconia nanoparticles using LVCC method using zirconium rode and different concentrations of Oxygen. The obtained results show that the prepared samples in the presence of 2.5and 20% O2 found to be tetragonal zirconia nanoparticles and its grain size was ranged between 2 to 8nm. On the other hand the He product was found to be hexagonal zirconium nanoparticles and its grain size was ranged between 5 to 7nm. The catalytic activity after doping with different concentration of palladium shows that the best catalyst is 2.5%O2-ZrO2 product doped by 20% Pd thus it completely oxidize CO to CO2 at 116 °C, this because the grain size of 2.5%O2-ZrO2 product was ranged between 2 to 3nm and this gave higher catalytic activity towards CO oxidation.
The fourth part of this chapter contains synthesis of zirconia nanoparticles using single stage microemulsion method. In this part three surfactants were used for the synthesis of zirconia nanoparticles includes AOT, CTAB and Oleylamine. The obtained results show that the particle size of Oleylamine zirconia was the smallest one but the catalytic activity of the doped sample with 5% Pd was less than doped CTAB zirconia with 5% Pd thus CTAB-ZrO2-5% Pd completely oxidize CO to CO2 at temperature degree 173 °C. So that CTAB was used for the preparation of ceria and ceria zirconia nanoalloy and the results show that the catalytic activity of the Ce0.5Zr0.5O2-5% Pd is better than both CeO2-5% Pd and ZrO2-5% Pd thus it completely oxidize CO to CO2 at temperature degree 130 °C.
Number of experiments was also done to show the effect of adding different percentage of graphene oxide to the previously as prepared CTAB products doped with 5% Pd. The obtained results show that the addition of 10% GO to the as prepared samples greatly affects on their catalytic activity and the best catalyst composition for CO oxidation was found to be Ce0.5Zr0.5O2-5% Pd-10% GO thus it completely oxidize CO at temperature degree 78.4°C.