الفهرس 
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Abstract
Graphene oxide is synthesized by Hummers method from graphite. Graphene is
prepared using three different methods after the chemical reduction of graphene
oxide. Then covalent and noncovalent functionalization are achieved for the
graphene surface by different amines as aniline and 1,6-diaminohexane. Silver
nanoparticles (AgNPs) were deposited on the surface of the functionalized
graphene during the synthesis process through the chemical reduction of silver
nitrate (AgNO3) by hydrazine hydrate. The disinfection effect was successfully
tested against total and fecal coliforms found in water samples from different
regions in Egypt.
The changes in surface functionalities and bonding nature were studied by X-ray
diffraction (XRD), Raman spectroscopy, nuclear magnetic resonance (NMR)
and infrared spectroscopy (IR). The morphology and size distribution were
studied by high resolution transmission electron microscopy (HRTEM) and
scanning electron microscopy (SEM), where the successful immobilization of
silver nanoparticles on the graphene surface was studied.
The following summarizes the experimental work undertaken in this thesis.
1- Preparation of graphene oxide
Graphite is converted chemically to graphene oxide following Hummers Offman
method (1) according to:
Graphite + H2SO4 (conc, 98%) + KMnO4+ NaNO3
Graphene oxide.
2- Preparation of graphene
Graphene is prepared chemically from graphene oxide (graphene-COOH) or
graphite oxide (as will be explained later) according to the following:
Graphene oxide or graphite oxide (graphene-COOH)
Graphene-CH2OH
First method
Graphite oxide(graphene-COOH) + NH4OH 30%
Graphene-CH2OH
Second method
Graphene oxide (graphene-COOH) + NH2C6H5+ NH2NH2HCl
Third method
Graphene oxide (graphene-COOH) + NH2NH2.H2O
3- Preparation of graphene functionalized by aniline and silver
nanoparticles:
First method: (noncovalent functionalization)
Reaction of aniline, silver nitrate and hydrazine hydrate with graphene oxide:
(Graphene-COOH)+ NH2C6H5 + AgNO3 + NH2NH2.H2O →
Graphene-COOH….. NH2C6H5…..AgNPs
Second method: (noncovalent functionalization)
Reaction of aniline, silver nitrate, hydrazine hydrate with graphene while
heating:
Graphene + NH2C6H5 + AgNO3 + NH2NH2.H2O
Graphene….. NH2C6H5…..AgNPs
Third method: (covalent functionalization)
Reaction of graphene oxide with thionyl chloride, aniline, silver nitrate and
hydrazine hydrate while heating in closed system:
Graphene-COOH+ SOCl2 Graphene-COCl
Graphene-COCl + NH2C6H5 → Graphene-CONH-C6H5
Graphene-CONH-C6H5 + AgNO3 + NH2NH2.H2O → Graphene-
CONH-C6H5…..AgNPs
4- Preparation of graphene functionalized by 1, 6-diaminohexane
and silver nanoparticles:
First method (noncovalent functionalization)
Reaction of graphene with hydrochloric acid, 1, 6-diaminohexane, silver nitrate
and hydrazine hydrate according to:
Graphene + HCl 30 % solution + H2NCH2─ (CH2)4─CH2NH2 +
AgNO3 + NH2NH2.H2O → Graphene….. NH2 (CH2) 6 NH2 …..AgNPs Second method (covalent functionalization)
Reaction of graphene oxide with thionyl chloride, 1, 6-diaminohexane, silver
nitrate and hydrazine hydrate while heating in closed system:
Graphene-COOH+ SOCl2 Graphene-COCl
Graphene-COCl + NH2CH2CH2CH2CH2CH2CH2NH2 →
Graphene-CONH─(CH2)6 ─NHCO-Graphene
Graphene-CONH-(CH2)6-NHCO-Graphene + AgNO3 + NH2NH2.H2O
→ Graphene-CONH- (CH2) 6 -NHCO-Graphene…..AgNPs
5- Bacterial infection test
Three ”untreated” infected water samples from three different regions in
Benisweef governorate were treated according to: 0.1 g graphene aniline /silver
nanocomposite /100 mL ” untreated ” water. This results in complete
disinfection for all samples. Also, 0.1 g graphene 1,6-diaminohexane /silver
nanocomposite /100 mL ” untreated ” water succeeded in disinfecting the water
samples from Bahr El-Bakar and Kochainer sewages. Bacterial infection tests
were conducted in the central laboratories of the Nile Research Institute of the
National Water Research Center in Egypt according to the following procedure:
Fecal coliform.
Fecal coliforms density was determined using seven hours fecal coliforms test
and applying membrane filter technique according to standard method (APHA,
1989). M-7h/FC ingredients were heated in boiling water bath then cooled to
55°C and pH value was adjusted to 7.3 before pouring in Petri dishes. After
incubation at 41.5°C for 7 hours, yellow colonies were counted as fecal coliform
bacteria.
Stock solutions were prepared using the appropriate solvent as indicated or
distilled water. Polluted (infected) water samples were collected according to
environmental procedures following environmental protection agency
regulations using sterilized glass containers. The samples were kept at low
temperatures in ice bath and delivered to the laboratory for immediate testing.
Infected water samples were collected from the Khour, mixing zone and the
river, all from Benisweef governorate (Elwasta area, five kilometers along the
Nile river from the 82.5 to 87.5 kilometers of the Nile river) and the samples
collected from Bahr El-Bakar and Kochainer sewage water.