الفهرس 
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Abstract
Summary
Preparation and Analytical Studies on Nanosized Calcium and Strontium Aluminate Nanoparticles
This study covered the following points
Chapter 1: Introduction and literature review
It includes general introduction about nanotechnology, types of nanomaterials, different methods for preparation of nanomaterials, properties of nanomaterials, applications of nanotechnology, toxicity of nanomaterials, water treatment, effect of heavy metals on human health, source of heavy metals in wastewater, different methods for removal of heavy metal from wastewater, and applications of nanomaterial in treatment of wastewater. It also includes different methods for the synthesis of calcium oxide, strontium oxide, aluminum oxide, calcium aluminate, strontium aluminate, and calcium strontium aluminate nanoparticles and their different applications.
Chapter 2: Materials and methods
It describes the materials and chemicals used in this study. It also explains the methods and pathways used for the preparation of nanoparticles like metals oxide and metals aluminate. It describes the synthesis of metal oxide like CaO, SrO, and Al2O3 nanoparticles and metal aluminate like CaAl2O4, SrAl2O4, and Ca1.93Sr1.07Al2O6 nanoparticles. These substances were prepared using a solution combustion method. Moreover, this chapter describe also several instrument utilized in this study such as X-ray diffractometry, thermogravimetric analysis, fourier transform infra-red spectroscopy, scanning electron microscope, inductively coupled plasma-optical emission spectrometer, transmission electron microscope, etc. used for the identification of the morphological, chemical characteristics of the prepared materials.
Furthermore, it describes the performed experiments and tests including adsorption experiments for the removal of heavy metals from wastewater.
Chapter 3: Results and discussion
This chapter consists of three parts discussing the results of this study
*Part one: Metals oxide such as calcium oxide (CaO),strontium oxide(SrO), and aluminum oxide (Al2O3) nanoparticle were prepared from metal nitrates and organic fuels like urea (A), glycine (B), and mixture of urea and glycine (C) with molar ratio (1: 1.667), (1: 1.111), and (1: 1.389), respectively the burnt samples were calcined at 700 ºC for 2h to obtained CaO NPs, 1000 ºC for 1h to obtained SrO NPs, 1000 ºC to obtained α-Al2O3. The prepared CaO, SrO, Al2O3 nanoparticles were characterized as follows
1- The XRD pattern of CaO showed the average crystallite size (D) was found to be 19.6, 19.8, and 18.7 nm for A700, B700, and C700 calcium oxide NPs samples calcined at 700 ºC for 2h, respectively. The XRD pattern of SrO showed the average crystallite size (D) was found to be 49.6, 47.8, and 42.7 nm for A1000, B1000, and C1000 SrO NPs. he XRD pattern of Al2O3 displayed that the estimated average crystallite sizes are found to be 6.45, 5.8, and 4.2 nm for (A800), (B800), and (C800) γ-Al2O3 nanoparticles, respectively. Also, the estimated average crystallite sizes are found to be 19, 15, and 12 nm for (A1000), (B1000), and (C1000) α-Al2O3 nanoparticles, respectively.
2- TGA/DTG analysis to obtained CaO, SrO, and α-Al2O3 showed that the decomposition of the burnt samples occurred in three, four, and four steps, respectively.
3- FT-IR spectra of CaO NPs, displayed a sharp band at 3650 cm-1 related to the O–H bonds of remaining hydroxide and band at 557 cm-1 identified the vibration of the Ca–O bond, FT-IR spectra of SrO NPs displayed bands at 607 cm-1, 705 cm-1, and 857 cm-1 are related to bending vibrations of Sr-O and band at 1036 cm−1 related to stretching vibrations of Sr–O–Sr, and FTIR spectra of Ɣ-Al2O3 displayed two broad vibrational bands at 552 and 842 cm−1 assigned to Al–O stretching vibrations in an octahedral coordination (AlO6) and a tetrahedral coordination (AlO4) sites, respectively. Also, the FTIR spectra of α-Al2O3 displayed vibrational bands at 639.3, 588.19, 495.62, and 449.34 cm−1
4- SEM micrograph show that α-Al2O3 product is composed of agglomeration of irregular and leave-like morphologies and the TEM image of the α-Al2O3 product revealed that the alumina product consists of hexagonal and irregular particles and also showed that the α-alumina product is not totally agglomerated and somewhat dispersed
*Part two: - Metal aluminate such as calcium aluminate (CaAl2O4) and strontium aluminate (SrAl2O4) nanoparticle were prepared from Metal nitrates with organic fuels like urea (A), glycine (B), and mixture of urea and glycine (C) with molar ratio (1: 2: 6.67), (1: 1: 2: 4.44), and (1: 2: 5: 1.11), respectively. The burnt samples were calcined at 800 and 1000 ºC to obtain CaAl2O4 and SrAl2O4 NPs, respectively. On the other hand calcium strontium aluminate (Ca1.93Sr1.07Al2O6) was prepared using calcium nitrate, strontium nitrate, aluminum nitrate, and the above fuels with molar ratio (2: 1: 2: 6.67),(2: 1: 2: 4.44), and (2: 1: 2: 5: 1.11), respectively. The burnt samples were calcined at 900 ºC to obtain the required nanoparticles.
The prepared CaAl2O4, SrAl2O4, and Ca1.93Sr1.07Al2O6 nanoparticles were characterized as follows:
1- The XRD pattern of CaAl2O4 showed that the average crystallite size (D) was found to be 40.4, 38.8, and 33.7 nm for A800, B800, and C800 calcium aluminate NPs samples calcined at 800 ºC for 2h, respectively, XRD pattern of SrAl2O4 showed the average crystallite size (D) was found to be 27, 30, and 25 nm for A1000, B1000, and C1000 strontium aluminate NPs samples calcined at 1000 ºC for 1h, respectively, and XRD pattern of Ca1.93Sr1.07Al2O6 showed the average crystallite size (D) was found to be 26.4, 28.5, and 12.6 nm for A900, B900, and C900 calcium strontium aluminate NPs samples calcined at 900 ºC for 2h, respectively.
2- TGA analysis. It was observed that the thermal decomposition process occurred in three steps to obtain CaAl2O4 and SrAl2O4 NPs but the thermal decomposition process occurred in two steps to obtain Ca1.93Sr1.07Al2O6 NPs.
3- FT-IR spectra of CaAl2O4 NPs showed a band at 823 cm-1, 500–900 cm-1 and 400–500 cm-1 are assigned to the stretching frequency of AlO4, Al–O, and Ca–O, respectively, FT-IR spectra of SrAl2O4 NPs showed specific bands at 850 cm-1 and 777 cm-1 assigned to stretching vibrations of AlO4 and bands at 512 and 647 cm-1 attributed to the Sr–O vibrations, and band appears at 415 cm-1 related to symmetric bonding of O-Al-O, and FT-IR spectra of Ca1.93Sr1.07Al2O6 NPs showed bands at 400–1000 cm-1 assigned to M-O, bands at 750–800, and 500–700 cm−1 assigned to the Al–O vibrations of tetrahedral (AlO4), and octahedral (AlO6), respectively.
1- SEM micrograph shown that CaAl2O4, SrAl2O4, and Ca1.93Sr1.07Al2O6 powders were composed of agglomerates small clusters with crystal-like structure, non-uniform shapes and size,
2- TEM micrograph show that CaAl2O4 and SrAl2O4 powders were composed of spherical and irregular particles of an average particle size of 30-50 nm and 25-30 nm, respectively.
*Part three: CaAl2O4 NPs and SrAl2O4 NPs are used as adsorbents for the removal of heavy metals like: As(Ш), Cd(II), Pb(II), and Ni(II) ions and give the following results:
1- The optimum pH value were 5, 8, 3:5, 7 for the removal of Pb(II) Cd(II), As(III), and Ni(II) ion by CaAl2O4 nanoparticles, respectively. The optimum pH value were 6 for removal of Pb(II) and Cd(II), and was 7 for the removal of As(III) and Ni(II) ion by SrAl2O4 nanoparticles, respectively
2- The removal efficiencies of Cd (II), Pb(II), As(III), and Ni (II) ions were increased gradually as contact time increased in case of using CaAl2O4 and SrAl2O4 nanoparticles as adsorbent. The optimum time for removal of Pb(II), As(III), and Ni(II) was 30 min and optimum time for the removal of Cd(II) was 120 min, using CaAl2O4 nanoparticles used as adsorbent. The optimum time for the removal of Pb(II), Cd(II), and Ni(II) was 45 min and for the removal of As(III) was 120 min, using SrAl2O4 nanoparticles as an adsorbent in batch experimental.
3- The optimum CaAl2O4 nanoparticles dose for the removal of Pb(II), As(III), Ni(II), and Cd(II) was 2 g.L-1 in batch experimental. The optimum SrAl2O4 nanoparticles dose for the removal of Pb(II), Ni(II), and Cd II) was 2 g.L-1 and the optimum SrAl2O4 nanoparticles dose for removal of As(III) was 4 g.L-1.
4- The removal efficiencies of Cd(II), Pb(II), Ni(II), and As(III) ions decreased by increasing initial metal ions concentration 10-100mg.L-1 in case of using CaAl2O4 and SrAl2O4 as adsorbents.
5- The small b values in the Langmuir indicate a strong binding of Cd(II), Pb(II), As(III), and Ni(II) ions to both SrAl2O4 and CaAl2O4 nanoparticles surface.
6- The correlation coefficients (𝑅2) values for Freundlich isotherm are higher than those for Langmuir isotherm model and Dubinin–Radushkevich (D–R). Therefore, the equilibrium sorption fitted well Freundlich isotherm. Thus, the adsorption of Ni(II), As(III), Pb(II), and Cd(II) ions onto CaAl2O4 and SrAl2O4 nanoparticles follow a multilayer adsorption process and the adsorption isotherms followed Freundlich model.
7- The values of correlation coefficients (𝑹𝟐) showed that the pseudo-second-order equation fitted the data better than those of the pseudo-first-order for As(III), Ni(II), Pb(II), and Cd(II) as CaAl2O4 and SrAl2O4 nanoparticles used as adsorbents.
8- The adsorption of As(III), Ni(II), Pb(II), and Cd(II) ions on CaAl2O4 and SrAl2O4 nanoparticles as adsorbent followed pseu