الفهرس 
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Abstract
EThe thesis aims to fabricate some simple metal oxides (ZrO2 and TiO2) and nanocomposites (ZrO2/TiO2) from the synthesized sample. The simple oxides and nanocomposites have been characterized by using different instruments. The prepared oxides have been applied to degrade crystal violet and methylene blue dyes in aqueous solutions. Various factors affecting on the degradation of the dyes were studied. The thesis consists of three main chapters:
Chapter 1: Introduction
The first chapter is an introduction about water pollution, water treatment method, definition of nanomaterials and the fabrication techniques of nanomaterials as well as their applications in different fields. This chapter also includes literature survey on the previous work performed on the simple and mixed metal oxides and their various applications such as water purification.
Chapter 2: Experimental
This chapter includes the description of the materials, reagents, and the methods which were used for the synthesis of simple and composite. Preparation of zirconium oxide (ZrO2) nanoparticles via combustion method using different fuels such as (CA, EG and CE) after calcination at 700 oC for 30 min. Preparation of titanium oxide (TiO2) nanoparticles via combustion method using different fuels such as (CA, EG and CE) after calcination at 500 o C for 1 h. Preparation of TiO2/ZrO2 nanocomposites were synthesized from the obtained ZrO2 and TiO2 nonoparticles using ultrasonication process for 15 min. The obtained nanocomposites were dried at 80 oC for 2 h followed by calcination at 700 oC for 1h.
This chapter contains the instrumental tools which are used in the characterization of the synthesized simple and composite materials. It includes the description of the method which is used for degredation of dyes from aqueous media.
Chapter 3: Results and discussion
This chapter contains the discussion and results of the extracted results. It can be divided into two main parts.
The first part
The first part describes the characterization of the obtained simple and mixed metal oxides nanocomposites by different tools such as thermal analysis (TG-DTA), powder X-ray (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS) and UV-Vis spectrophotometer.
The extracted results showed that the obtained zirconium oxide using auto-combustion method in the nanometer range. The average crystalline size ware determined using X-ray 9, 4.7 and 7.3 for the ZCA, ZEG and ZCE samples, respectively. The transmission electron microscopy showed that the crystalline regular and irregular spherical shape with agglomeration. FT-IR spectra appeared peaks at 500-780cm-1, which related to the zirconium oxide nanoparticles.
Extracted data showed that obtained titanium oxide using combustion method in the nanometer range. The determined average crystalline size using X-ray powder diffraction were found to be 6.4, 14.4 and 6.8 nm for the TCA, TEG and TCE samples, respectively. FT-IR spectra appeared peaks at 400-800 cm-1, which related to the titanium oxide nanoparticles. The results showed that ZrO2/TiO2 nanocomposites were synthesized in the nanometer range. XRD results confirmed the presence of the obtained nanocomposites without any impurities, as well as the crystalline size were in the range 20, 19, 17and 10 nm for ZT11, ZT12, ZT21 and ZT41 samples, respectively. The transmission electron microscopy revealed that the particles have spherical and unspherical shapes with agglomeration as result of the presence a mixture of zirconium and titanium oxides nanocmposite. FT-IR spectra showed the strong absorption bands at 480, 500, 600 and 650 cm−1 for all samples are corresponding to Ti-O and Zr-O stretching vibration mode of ZrO2 and TiO2 nanoparticles.
The second part
The second part include the photocatalytic degradation data for the crystal violet and methylene blue in aqueous media using the synthesized ZrO2, TiO2 and ZrO2 / TiO2 nanocompsite. This part includes the results and discussion of the factors affecting on the degradation of the dye from aqueous solutions such as contact time and effect of dose. The optimum conditions for the degradation process were as follow:
1- The contact time for the degradation of crystal violet using the synthesized samples takes about 135 min. the degradation of crystal violet increases with the raise of the dose of the synthesized simple and mixed oxide. The degradation of crystal violet dye over the synthesized sample fitted the pseudo first order model. Finally, the degradation of crystal violet dye over the fabricated sample and mixed sample.
2- The contact time for the degradation of methylene blue using the synthesized samples takes about 135 min. the degradation of methylene blue increases with the raise of the dose of the synthesized simple and mixed oxide. The degradation of methylene blue dye over the synthesized sample fitted the pseudo first order model. Finally, the degradation of methylene blue dye over the fabricated sample and mixed sample.