الفهرس 
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Abstract
The present work is focused on the preparation of nano silver particles
supported on substrate. The characterization and study of adsorptive
properties of the resulted composites towards the adsorption of dyes such
as Allura Red, acid green 25and acid blue 29 was obtained and included
in the thesis which is consisted of three main chapters.
The first chapter represents a literature review on the water pollution. Its
sources and impacts on the aquatic life and humans are included. The
methods of water treatment and the advantages of silver nanoparticles on
metal oxides as adsorbents are also added.
The second chapter includes the experimental part, which describes the
materials, instruments, and synthesis of materials under investigation.
The way of measurements of dyes removal by adsorption was described.
The third chapter comprises the results and discussion. It describes the
characterization results of prepared composites, the removal kinetics of
Allura Red (AR), acid green 25(AG25) and acid blue 29(AB29) dyes
with silica/Ag, magnetite/Ag, and alumina/Ag composites. It was found
that silica/Ag is the most active adsorbent regarding the removal behavior
of dyes. Furthermore, when silica/Ag composite was prepared under the
influence of glucose, ascorbic acid, ethylene glycol, and glycine and
tested against dye adsorption revealed that silica/Ag-glu is the most
efficient. Therefore, this composite was entered into a detailed study with
dyes under variable reaction conditions, namely, the dye concentration,
adsorbent dose, pH, and temperature. It was found that the silica/Ag /dye
interaction proceeds via pseudo-second-order kinetics. The rate of
interaction and the equilibrium adsorption capacity (qe) increased with
increasing the composite dose, initial dye concentration, solution pH, and
temperature. The determined thermodynamic parameters revealed aspontaneous and endothermic nature of the adsorption process. The
positive value of ΔS° indicates the increasing randomness at the
composites/dye solution interface for the three dyes. The results of dye
removal were analyzed using the Langmuir, Freundlich, and Temkin
isotherms. The Langmuir isotherm was the best fitted one for adsorption
of all dyes onto the silica/Ag composite. In conclusion the removal of
dyes from aqueous solution by adsorption on the surface of the above
support/AgNPs composites can be considered efficient for environmental
applications.