الفهرس 
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Abstract
Summary and Conclusion In the present time, the organic dyes, which are used in many industries, such as papers, textile, pharmaceutical, food industries dyestuffs and plastic represent one of the most important sources of water pollution. As a result of its non-bio degradability and its high toxicity that affects human life and living organisms. In addition, the process of decomposition of dyes is very difficult due to their resistance to heat, light and oxidizing agents. Removing of many dyes from the waste water is a problematic process because of it good soluble in the water and non-biodegradable. There are several chemical, physical and biological methods for disposal of these dyes from wastewater using nanostructures. The objective of this work aims to elimination of methyl orange dye from water using pure titanium oxide and nitrogen, copper doped titanium oxideas well as using polyaniline and their composites with pure titanium oxide and nitrogen, copper doped titanium oxide. The physical properties of the pure materials and their composites with polyaniline are studied. The photocatalytic activity and adsorption efficiency of the obtained samples were studied. This thesis consists of four chapters:
Chapter 1: deals with a general introduction of the subject and literatures survey.
Chapter 2: concerns theoretical review and calculation methods used for analyzing the results of XRD to determine the crystallite sizes, UV-visible reflectance to calculate energy gap. Ac-conductivity, dielectric constant (ε`), dielectric loss (ε``), complex impedance (Z’), adsorption isotherms and kinetic parameters of adsorption process were mentioned.
Chapter 3: includes the materials used in this work, the experimental procedures for the preparation of nano-TiO2, Nitrogen-doped TiO2 powders, Cu doped TiO2, polyaniline and their nanocomposites.
It also contains the techniques used for characterization: X-ray diffraction (XRD), Fourіer transform іnfrared (FTІR), dіffuse reflectance UV-Vіs spectroscopy technique (UV- Vіs DRS), Photolumіnescence spectroscopy (PL) and transmission electron microscopy (TEM), sensitizing testing method. This chapter includes also the techniques that are used for samples characterization including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), Photoluminscence spectroscopy (PL), Thermal gravimetric analysis (TGA) and N2-adsorption isotherm. It contains also the measurements of electrical properties (Ac-conductivity, dielectric constant, dielectric loss, complex impedance) and photocatalytic activity. The adsorption isotherms measurements were included.
Chapter 4: deals with the results and discussions of the all obtained results and divided to two parts
Part A: In this part, pure TiO2 and Cu or N doped TiO2 nanoparticles were synthesize through sol-gel method with different ratios of N (50% and 100%), and of Cu (0.1, 0.2, 0.3, 0.6 wt%). The effect of the doping process was studied through different characterization tools such as XRD, FT-IR spectroscopy, UV–visible absorption spectra and photoluminescence spectra. The effect of doping was studied and discussed on the photocatalytic activity of samples.
The main results in this part:
It was found that:
• Pure TiO2 and all Cu-doped TiO2 samples show the same diffraction peaks attributed to the anatase structureas a main phase in presence of brookite phase in samples with 0.2, 0.3% and CuO of monoclinic structure in sample with 0.6%.
• All N-doped TiO2 samples show the formation of anatase structure.
• The crystallite sizes of all samples ranged from 11.9 nm to 16.4 nm.
• The shift of peaks position and increasing the lattice parameter (c) and cell volumes on doping with N and Cu indication the presence of Cu and N ions in the lattice of TiO2.
• All Cu and N-doped TiO2 samples show extended absorption to visible light region compared to pure TiO2.
• The determined energy gap (Eg) values of all doped samples were lower than that of pure TiO2 sample and ranged from 3.61 eV to 2.61 eV.
• Photoluminescence results shows that the TiO2 samples doped with 100% N and 0.6% Cu have the lowest PL intensity compared to pure TiO2 and other samples which indicate that Cu and N-doping markedly enhances the charge separation of photogenerated carriers of TiO2 nanoparticles suggesting their high photocatalytic activity.
• The order of the photocatalytic activity of the Cu doped samples toward degradation of methyl orange dye was TiO2 < Cu(0.1)/Ti < Cu(0.2)/Ti < Cu(0.3)/Ti < Cu(0.6)/Ti.
• The order of the photocatalytic activity of the N doped samples toward degradation of methyl orange dye was TiO2 < N(50)/Ti < N(100)/Ti.
from all previous results Cu(0.6)/Ti and N(100)/Ti samples shows the highest photocatalytic activity toward degradation of MO dye.
Part B:
In this part, different nonocomposites are prepared from polyaniline with pure TiO2 and N, Cu doped TiO2. where titanium oxide samples doped with 0.6 wt% Copper (Cu(0.6)/Ti) and titanium oxide sample doped with 100% Nitrogen (N(100)/Ti) were selected for their high catalytic activity and their distinctive properties which were studied in the previous part A. Different concentrations of pure and doped titanium oxide were prepared namely 5, 15 and 25 wt%. The synthesized nanocomposites were characterized using transmission electron microscopy (TEM), X–ray diffractometry (XRD), thermogravimetric analyses (TGA), FT-IR spectroscopy, N2-adsorption isotherm and UV–visible absorption spectra. The effect of the presence of pure and doped TiO2 nanoparticles on the thermal, optical and electrical properties will be discussed. The removal of MO dye by adsorption process was studied.
The main general conclusions for this part are:
• Polyaniline, Cu/Ti(5)/PANI, Cu/Ti(15)/PANI and Cu/Ti(25)/PANI, Ti(5)/PANI, Ti(15)/PANI and Ti(25)/PANI nanocomposites were prepared by in-situ polymerization.
• The XRD patterns of all prepared nanocomposites show both the characteristic peaks of TiO2 and broad diffraction peaks of PANI.
• FT-IR spectra of composites confirm the interaction of pure and Cu, N doped TiO2 and polyaniline chains.
• Thermal analysis results suggest enhancement the thermal stability of Ti(25)/PANI, CuTi(5)/PANI and NTi(15)/PANI nanocomposites compared to PANI. This reduction in weight loss was due to a strong interaction at the interface of TiO2, N/TiO2 and Cu/TiO2 and PANI.
• The TEM images of PANI, Ti(25)/PANI, CuTi(5)/PANI and NTi(15)/PANI nanocomposites shows rod like structures.
• PANI, Ti(25)/PANI, CuTi(5)/PANI and NTi(15)/PANI nanocomposites shows reveals type IV with hysteresis loops of type H3, signifying the presence of mesoporous structures.
• Electrical properties
i. AC- conductivity was studied at 5 MHz for PANI, Ti(25)/ PANI, N Ti(15)/PANI and Cu Ti(5)/PANI.
ii. The three samples of nano pure and doped (Cu,N) TiO2 showed the following AC – conductivity value order at room temperature (303K): [ NTi(15)/PANI ; ơAC = 5.01x10-4 ohm-1.cm -1 > CuTi(5)/PANI ; ơAC = 3.16 x 10-4 ohm-1.cm -1 > Ti(25)/ PANI; ơAC = 2.04 x 10-4 ohm-1.cm -1 ]
iii. NTi(15)/PANI composite shows the highest values of dielectric constant compared to the other ones. The sample showed a value of )26(, while the others showed the following values order: Cu Ti(5)/PANI; 25 > Ti(25)/ PANI; 17 > PANI ; 3, at )303 K(.
• Adsorption process results shows:
i. The elimination capabilities of TiO2/polyaniline composites for removal of MO dye in (20 min) were ordered as: Ti(25)/PANI (94.1%) > Ti(5)/PANI > Ti(15)/PANI > PANI.
ii. The elimination capabilities of NTiO2/polyaniline composites for removal of MO dye at (20 min) were ordered as: NTi(15)/PANI > NTi(25)/PANI > NTi(5)/PANI > PANI.
iii. The elimination capabilities of CuTiO2/polyaniline composites for removal of MO dye at (20 min) were ordered as: CuTi(5)/PANI > CuTi(25)/PANI > CuTi(15)/PANI > PANI.
iv. from above results it was found that the removal efficiency of dye in (20 min) on different composites that shows the highest adsorption capacity compared to PANI were ordered as: Ti(25)/PANI (94.1%) > CuTi(5)/PANI (85.1%) > NTi(15)/PANI (83%) > PANI (68.4%).
v. The optimum conditions are initial concentration of MO dye is (120 ppm), (pH = 7), adsorbent load = 0.1 g/L at room temperature.
vi. Freundlich and Langmuir and Temkin model models were applied to analyze the obtained experimental adsorption data on Ti(25)/PANI, CuTi(5)/PANI and NTi(15)/PANI composites compared to PANI.
vii. The obtained experimental adsorption data on PANI and NTi(15)/PANI samples well fit the Freundlich model due to higher correlation coefficients (R2) (0.970 and 0.889) respectively.
viii. The obtained experimental adsorption data on Ti(25)/PANI and CuTi(5)/PANI samples well fit the Langmuir model due to higher correlation coefficients (R2) (0.963 and 0.997) respectively.
ix. The pseudo-first-order, pseudo-second order, Elovich and intraparticle diffusion models were examined to assess the mechanism of the adsorption process.
x. from kinetics results, The results displays that the pseudo-second-order kinetic model exhibited the best correlation coefficient for the adsorption of dye on the pure PANI, Ti/PANI, Ti(Cu)/PANI and Ti(N)/PANI nanocomposites compared to the other models.