الفهرس 
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Abstract
Water resources in Egypt are exposed to many risks that threaten the health of all living organisms. Di-butyl phthalate is one of the most dangerous organic compounds that pollute water and poses a potential threat to all living organisms and ecosystems, so it requires extensive attention from scholars. One of the important objects of the current study is to find effective, rapid and economic methods and technologies to remove this substance.
A- Water samples were collected from different water sources (Tap-water, Ground-water and surface water) and localities (Surface water samples of River Nile were collected from Assiut, Sohag and Minia Governorates while tap and ground water samples were collected from poultry farms located in Assiut Governorate) to investigate the presence of Di-butyl phthalate as an organic pollutant.
B- DBP was detected in all water samples with mean concentrations in ground, tap and surface water samples that were 0.509±0.04, 0.373±0.07 and 0.491±0.12, respectively.
C- The present study is based on the synthesis of different nanomaterials for their application as adsorbent materials for the removal of DBP from water samples. Development of seven nanomaterials were carried out including Fe3O4@NH2, Fe3O4@NH2@CMC, Fe3O4@NH2@CMC@r-GO, r-GO, Fe3O4@CS, Fe3O4@CS@CMC and Fe3O4@CS@CMC@r-GO with removal perentages equaled 72.31 ± 1.13, 90.89 ± 0.32, 96.24 ± 0.16, 93.61 ± 0.25, 68.41 ± 0.15, 79.83 ± 0.06 and 86.13 ± 0.14, respectively.
D- from the obtained results, it had chosen both Fe3O4@NH2@CMC and Fe3O4@NH2@CMC@r-GO NCs for removal of DBP from water samples with applying the following steps:
- Synthesis and characterization of the magnetic graphene oxide nanocomposite using HRTEM ”High Resolution Transmission Electron Micrograph coupled with Energy dispersive spectroscopy”, XRD ”X-ray diffraction”, FTIR ”Fourier transfer infrared” and Zeta techniques.
- Experimental design was done to study the effect of different parameters as pH, contact time, initial DBP concentration, dose of adsorbent and temperature on efficiency of adsorption and adsorption rate.
- The potential reusability and ability of nano- adsorbents were used.
- Real application of the two nanocomposites in water samples was adopted.
1- Synthesis and characterization of the magnetic based nanocomposites using HRTEM ”High Resolution Transmission Electron Micrograph coupled with Energy dispersive spectroscopy”, XRD ”X-ray diffraction”, FTIR ”Fourier transfer infrared” and Zeta techniques.
1-a. Synthesis and characterization of Fe3O4@NH2@CMC nanocomposite:
• The synthesized Fe3O4@NH2@CMC was cubic and rod shape structure estimated from the HR-TEM images, with averages size of 50 nm. Magnetite NPs was confirmed by the presence of Carbon (C), oxygen, iron, Sodium and Chloride elements as 58.83, 38.47, 1.47, 0.70 and 0.53%, respectively.
• Crystalline structures and confirmations of the elemental analysis were demonstrated from the EDS spectra.
• FTIR spectrum of modified Fe3O4 nanoparticles showed the collection of the characteristic absorption bands of CMC and Fe3O4, which indicated the successful binding of CMC to Fe3O4 nanoparticles.
• CMC molecules were successfully intercalated into the spacing of layers of Fe3O4 as estimated from XRD.
• from zeta potential, the particle size was equal to 58.77 nm and zeta potential equals +38.5 mv that mean the present novel ”Fe3O4@NH2@CMC” nanocomposite was more stable material.
1-b. Synthesis and characterization of Fe3O4@NH2@CMC@r-GO nanocomposite:
• The average size of synthesized Fe3O4@NH2@CMC@r-GO was 7.87 – 13.29 nm was estimated from the HR-TEM images.
• Crystalline structures and confirmations of the elemental analysis were demonstrated from the EDS spectra.
• Impregnation of an approximately the same particles sizes of Fe3O4 in carboxy methyl cellulose and reduced graphene oxide was carried out.
• FTIR spectrum that confirmed the linkage between the different functional groups to obtain one novel nanocomposite was used in the removal of DBP from aqueous solution.
• from zeta potential that equaled -31.1 mv which proved that the synthesized novel ”Fe3O4@NH2@CMC” nanocomposite was a stable material due to its value is higher than ± 30 mV.
2- Experimental design to study the effect of different parameters as pH, contact time, initial DBP concentration, dose of adsorbent and temperature on efficiency of adsorption and adsorption rate:
• To determine the optimum conditions of pH, dose and temperature for nanocomposite.
• 2-a. The optimum conditions of Fe3O4@NH2@CMC were at pH 7.37, and 37.5° C, for 60 min.
• 2-b. While, the optimum conditions of Fe3O4@NH2@CMC@r-GO were at pH 8.6, and 50° C for 4 hours.
3- The potential reusability and ability of nano- adsorbents used.
from the obtained data; it could summarize that Fe3O4@NH2@CMC nanocomposite could be reused for successive five cycles where the removal percentage for DBP was 99.234% at the fifth cycle which had indicated the high efficient adsorption force of that nanocomposite after cycles of reusability. Furthermore, Fe3O4@NH2@CMC@r-GO nanocomposite could be reused for five cycles with removal % that equaled 98.99% at the fifth cycle indicating the high efficient and economic advantages of nanocomposite used.
4- Real application of the two nanocomposites in water samples:
The mean value of residual concentrations of DBP after real application for tap, ground and surface water samples were 0.030 ± 0.020, 0.010 ± 0.00 and 0.0112 ± 0.00 ppm, respectively, with a mean value of removal % equaled 99.625 ±0.21, 99.749 ± 0.15 and 99.883±0.04 % for tap, ground and surface water samples, respectively.
- Moreover, the obtained results revealed that there were highly significant values before and after application of Fe3O4@NH2@CMC NC in spiked water samples for tap, ground, poultry farm drinking water and surface water samples.
-The second concerned nanocomposite was ”Fe3O4@NH2@CMC@rGO” for removal of DBP in real application (optimum conditions were set as pH 8.6 in 250 mL flasks containing 0.1 gm/L of Fe3O4@NH2@CMC@rGO NC as adsorbent, at 50° C, and shaking at 4000 rpm for 4 hours). The mean values of residual concentration of DBP after real application for tap, ground and surface water samples were 0.020±0.01, 0.030±0.010 and 0.020±0.010 ppm, respectively, with a mean value of removal % equaled 99.826±0.06, 99.929 ±0.02 and 99.826 ±0.06 for tap, ground and surface water samples, respectively.
The obtained results showed that there was a highly significant value before and after application of Fe3O4@NH2@CMC@rGO NC in spiked water samples for tap, ground, allover poultry farm drinking water and surface water samples.