الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
The work done in this study has been presented in five chapters as discussed in
the following text:
The first chapter gives the introduction where it discusses how heavy metal
pollution has become one of the most serious environmental problems today. The
treatment of heavy metals is of special concern due to their recalcitrance and
persistence in the environment. In recent years, various methods for heavy metal
removal from wastewater have been extensively studied. So the aim of this work to
study the adsorption as a method for the removal of some of these toxic heavy metals
and a literature review about the different types of techniques and adsorbents for the
removal of heavy metals especially copper and cadmium.
The second chapter gives the materials and methods where experimental
procedures, materials, chemicals, apparatus, instruments used and analytical
techniques are discussed in details.
The third chapter gives the results and discussion. It consists of two parts; the
first part explains the adsorption of Cu(II) ions and Cd(II) ions onto sesame husk. The
second part explains the adsorption of Cu(II) and Cd(II) ions onto modified almond
shells (comparative study).
In the first part, the removal of Cu(II) and Cd(II) ions was studied using
sesame husk as an adsorbent. The experiments were carried out in order to study the
effect of different parameters such as pH, contact time, adsorbent dose, initial metal
ion concentration, temperature and agitation speed. The results showed that, the
majority of the reaction was completed in the first 10-15 minutes and the maximum
Cu(II) and Cd(II) ions removal was observed. The optimum pH was found to be 6.0 in
case of Cu(II) ions while the optimum pH was found to be 5.0 in case of Cd(II) ions.
The study of thermodynamic parameters (ΔG°, ΔH° and ΔS°) showed that the
adsorption of Cu2+ and Cd2+ ions onto sesame husk was spontaneous, less random and
exothermic in nature. But for copper adsorption, the ΔG° value changed from negative
to positive value on increasing the temperature which means that the adsorption
reaction is non-feasible and non-spontaneous at higher temperature whereas for
cadmium, the adsorption process is spontaneous and the degree of spontaneity of the
reaction decrease with increasing temperature. Adsorption kinetics were studied using
pseudo first-order, pseudo second-order and intra-particle diffusion kinetic models at
different initial concentrations of the adsorbate. Pseudo second-order mechanism was
the best in fitting the experimental data. Adsorption isotherm models (Langmuir,
Freundlich and Dubinin-Radushkevich) were applied on data at different initial
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concentrations. Langmuir isotherm model was found to be the best in fitting the
experimental data which reveal the homogeneity of sesame husk surface. The
maximum adsorption capacity (qmax) was found to be 10.83 mg/g for copper ions and
38.91 mg/g for cadmium ions adsorption. Morphological study was done using SEM
to observe the changes on the surface of sesame husk before and after adsorption of
Cu(II) and Cd(II) ions. FT-IR spectra were used to study the participated functional
groups, on the surface of sesame husk, in removing Cu(II) and Cd(II) ions.
In the second part, the removal of Cu(II) and Cd(II) ions was studied using
modified almond shells (MAS) adsorbent. The experiments were carried out in order
to study the effect of different parameters such as pH, contact time, adsorbent dose,
initial metal ion concentration, temperature and agitation speed. The results showed
that, the majority of the reaction was completed in the first 15 minutes and the
maximum Cu(II) and Cd(II) ions removal was observed. The optimum pH was found
to be 6.0 in case of Cu(II) ions while the optimum pH was found to be 5.0 in case of
Cd(II) ions. The study of thermodynamic parameters (ΔG°, ΔH° and ΔS°) showed that
the adsorption of Cu2+ and Cd2+ ions onto MAS was spontaneous, less random and
exothermic in nature. But for both of copper and cadmium ions adsorption, the
absolute values of ΔG° decreased with the increase in temperature which refer that the
degree of spontaneity of the reaction decrease with increasing temperature.
Adsorption kinetics were studied using pseudo first-order, pseudo second-order and
intra-particle diffusion kinetic models at different initial concentrations of the
adsorbate. Pseudo second-order mechanism was the best in fitting the experimental
data. Adsorption isotherm models (Langmuir, Freundlich and Dubinin-Rdushkevich)
were applied on data at different initial concentrations. Langmuir isotherm model was
found to be the best in fitting the experimental data which reveal the homogeneity of
MAS surface. The maximum adsorption capacity (qmax) was found to be 46.73 mg/g
for copper ions and 35.84 mg/g for cadmium ions adsorption. Morphological study
was done using SEM to observe the changes on the surface of MAS before and after
adsorption of Cu(II) and Cd(II) ions. FT-IR spectra were used to study the
participated functional groups, on the surface of MAS, in removing Cu(II) and Cd(II)
ions.
The fourth chapter contains the cited references in this thesis. Finally, the
fifth chapter comprises the appendices which are located at the end of the thesis. The
appendix contains the experimental data for the two parts of the thesis.