الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
The thesis comprises four main chapters:
The thesis came in four main chapters, as follows:
Chapter (I): Introduction
It includes a brief presentation on the nanomagnetic adsorbent materials, especially nanomagnetite, covering the different techniques of preparation, characteristics and use for the purposes of removing heavy metal ions from aqueous solutions. It also includes the materials used to treat the surface of magnetite and the dual role of these materials as they are used to cover the surface and to prevent both the aggregation of nanoparticles and the effect of the medium. In addition to the possibility of modification of these surfaces to increase the efficiency of the magnetic adsorbent in removing the target metal ion. Modification was done by metal oxides such as silica, natural polymers, or organic compounds with a variety of functional groups or biomolecules. The introduction also showed gallic acid modified adsorbents.
Chapter II: Experimental
It is the experimental part of the message and it includes the chemicals used, their sources, methods of preparing solutions of binary ions salts for each of cobalt, zinc and cadmium, methods for their individual estimation using EDTA and the indicators used for this purpose, as well as an explanation of the methods of preparing the nanomagnetic adsorbents under study using the microwave technology, as well as a description of these adsorbents using FT-IR, XRD, and both SEM and TEM as well as pH meter, atomic absorption spectrometer and mechanical vibrator. In addition to showing how to study a number of active parameters to maximize the ability of the new magnetic adsorbents to separate and remove the target metal ions. In addition to how to recycle and apply to real water samples, including seawater, Nile River water, tap water and groundwater.
Chapter III: result and discussion
It is a review of the results obtained and discussed which came as follows:
• The results of the characterization showed the success of the process of preparing nanomagnetite particles coated with silica SCMNPs and the size of the particles in the range 11.7-24.81 nm with a mean size of 16.93 nm. This is as a primary adsorbing agent. As well as the covalent binding of gallic acid to the surface of these particles, producing the modified adsorbing agent SCMNPs-GA, keeping the nanoscale size, to fall in the range 11.5-25.41 nm with a mean size of 17.80 nm.
• The maximum capacity for adsorption of the metal ions under study was 3.115, 3.56, and 3.115 mmol/g of cadmium (II), zinc (II) and cobalt (II), respectively, using SCMNPs under optimal conditions, of pH = 5 for cadmium (II) and cobalt(II), pH = 6 for zinc(II), shaking time of 10 min, mass of 10 mg.
• The maximum capacity increased to reach 8.188, 8.455, 7.565 mmol/g for Cd(II), Zn(II), and Co(II), respectively, when using the SCMNPS-GA, at 2 min shaking time, with 10 mg mass of adsorbent and at the other optimum conditions mentioned above. This was attributed to the replacement of the Si-OH silanol group by the three hydroxylphenolate groups of the gallic acid covalently bonded via the amide -NH-CO-bond by using of 3-APTS.
• The results of measuring the effect of varying molar concentrations (0.1 0.3, and 0.5 M) of hydrochloric acid on the stability of the two magnetic nanoadsorbent showed a high degree of stability, where the loss in metal capacity values ranged between (0.0%, 1.5%, and 4.6%) for the SCMNPs and these values did not exceed 1 % with SCMNPs-GA. These results confirm the stability and strength of amide linkage compared to ester linkage and support the recycling and application process.
• The process of recycling has come for many times fast and simple due to the advantage of magnetic adsorbent that enables us to complete the separation process using an external magnetic field and without the need for filtering, drying and weighing as in the case for traditional non-magnetic adsorbents. Consequently, recycling times reach 7 to 10 cycles of sorption-desorption without loss in removal efficiency using 0.1 M HCL as desorbing agent and/or 0.1 M EDTA solution as a strong complexing agent.
• The results showed that the metal capacities of adsorbents as a function of the metal ion concentration and time agreed with the Freundlich model of adsorption, indicating surface heterogeneity, and the kinetics of the adsorption process came well with the pseudo –second order and has reached the value of the correlation coefficients of 1.0 or close to it.
• Promising results were obtained upon application both of SCMNPs and SCMNPs-GA for removal of ppm concentrations of Cd(II) ions, each study was added to samples of seawater, Nile river water, tap water and ground water, where the extraction percentage ranged from 95.0% to 97.5% when Cd(II) was removed using SCMNPs, and ranged from 95.0% to 99.5% when Cd(II) was removed using SCMNPs-GA.
• The adsorbents under study were distinguished when compared with other adsorbents, especially with regard to the short preparation time as well as the speed of adsorption, in addition to high metal adsorption capacity values. These results are in harmony with the size of the nanoparticles along with their high affinity for binding with the metal ions under studying.
Chapter IV: This part includes the references of the thesis.