الفهرس 
Chapter 1: IntroductionOnly 14 pages are availabe for public view
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Abstract
Cellulose derivatives were synthesized through an intermediary step of
chlorination before being functionalized with amino acids moiety (i.e., arginine and
glutamic). The sorbents (Arg-Cell and Glu-Cell) have been characterized by elemental
analysis, FTIR spectrometry, XRD and SEM-EDX analysis and TGA. In a second step,
the sorption properties of these materials were tested for recovery of U(VI) from
aqueous solution: pH effect, uptake kinetics and sorption isotherms were investigated.
The sorption efficiency increases with pH; this can be attributed to the deprotonation of
carboxylic acid and amine groups and to the formation of polynuclear poly-hydrolyzed
uranyl species. Sorption isotherms (fitted by the Langmuir equation) show sorption
capacities at saturation of the monolayer of 147 and 168 mg U g-1 for Arg-Cell and
Glu-Cell, respectively (compared to 78 mg U g-1 for cellulose); maximum sorption
capacities at equilibrium (experimental values) reach 138, 160 and 73.4 for Arg-Cell,
Glu-Cell and cellulose, respectively. Uranyl sorption is endothermic, spontaneous for
amino-acid derivatives of cellulose (contrary to exothermic for cellulose). Uptake
kinetics for the different sorbents are fitted by the pseudo-second order rate equation.
Uranium can be desorbed using sulfuric acid solutions and the sorbents can be recycled
for a minimum of five cycles of sorption/desorption: the decrease in sorption capacities
at the fifth cycle does not exceed 13 %. Finally, application of the bench scale results to
the extraction of uranium from Gattarian Granite uranium mineralization sample.
Uranium desorption efficiency attain 93.2, 92.4 and 87.6 % for maximum sorption
capacity of 128 109 and 39 mg/g for Glu-Cell, Arg-Cell and Cell, respectively; which
the actual efficiency is found to be 80, 78.09 and 53.42 % following the application on
the liquor solution of Gattarian Granite.