الفهرس 
Chapter (II)Only 14 pages are availabe for public view
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Abstract
In this study: we prepare four chelating resins. In the first one chitosan and bio-based activated carbon obtained from sugarcane bagasse biowaste were used for the synthesis of efficient sorbent for Cu(II) and Cd(II) ion via precipitation method. The prepared material was enriched with amino groups through grafting tetraethylenepentamine and tested for heavy metal remediation from water samples. These tests, explained by means of the most common sorption models, evidenced that the best performances were reached pointing out the promising application of the prepared sorbent for water purification treatments. The sorbent showed high metal ion sorption capacity with negligible influence of ion strength. The maximum sorption capacities reached 3.44 and 2.38 mmol g−1 for Cu(II) and Cd(II), respectively at 298 K.
In second, third and fourth resins we make Polymerization of chitosan in the presence of fine powder of apricot seeds and Preparation of amine form of the resins obtained by different materials :
R2 by Ethylenediamine.
R3 by L-Cysteine.
R4 by Glutaric acid.
We study the uptake behavior of the chelating resins obtained towards metal(Cu (II) and Cd (II) or for Cu(II), Fe(II), Mn(II) and Ni(II) ions in mixed aqueous solution and at different experimental conditions of pH, , time, temp. and metal ion concentration.
Thermodynamic parameters were evaluated through variation of temperature. The sorption is unfavorable at elevated temperatures. Metal ions were successfully desorbed using HNO3 solution .
To determine the sorption kinetics four models were used: the pseudo first order (PFORE) proposed by Lagergren , the pseudo second order (PSORE) used by Ho and McKay , the Fickian diffusion model by Weber and Morris and Elovich equation.
It can be concluded that the best fit of the experimental data is exhibited by the PSORE, Fickian diffusion model and Elovich equation in which the determination coefficient (R2) is higher than 0.98.PSORE gives the best fit for experimental data than other models.
The isotherms like Langmuir, Freundlich, Temkin and DubninRadushkevich (D-R) were used to fit the equilibrium data for metal ions sorption onto synthesized resins. These isotherms studies make known that the nature of the force of interaction between sorbent and sorbate. Langmuir isotherm is the most suitable sorption model when compared to Freundlich, The superimposition of fitted curves to experimental points on Figure (6) confirms these conclusions.
The uptake of Cu(II), Fe(II), Mn(II) and Ni(II) at different temperature from natural temperature (250C ) and reaching to temperature (500C). This means that the uptake of Cu(II), Fe(II), Mn(II) and Ni(II) on resin Chit-EDA@AS not affected by temperature.
The regeneration and recycling of the sorbent was finally tested.