A high-energy ball milling of magnetite nanoparticles with amino-phosphonic functionalized poly(glycidyl methacrylate) polymer is used for manufacturing a highly efficient magnetic sorbent for U(VI) sorption from aqueous solutions. The Uranyl ions were adsorbed through the binding with amine and phosphonic groups as confirmed by Fourier Transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses. The maximum sorption capacity (up to 270 mg U g À1) occurred at pH ¼ 3e4; Langmuir isotherm well describes the sorption process. Small-size particles allow achieving fast uptake (within z90 min of contact); and the kinetic profiles are modeled by the pseudo-second order rate equation. Uranium is successfully desorbed from loaded sorbent using 0.25 M NaHCO 3 solution: Sorbent can be recycled with minimal decrease in sorption and desorption efficiency for at least 6 cycles. The sorbent is efficiently used for U(VI) recovery from the acidic leachates of U-bearing ores (after precipitation pre-treatment). Sorption capacity approaches 190 mg U g À1 despite the presence of high concentrations of Fe and Si: the sorbent has a marked preference for U(VI) (confirmed by distribution ratios and selectivity coefficients).

The prepared amine-impregnated cellulose (AIC) was found to be an efficient adsorbent for uranium originated from El-Sebaiya phosphate ore. The impregenation process was carried out by copolymerization between pretreated cellulose and a mixture of (tri-ethyl amine and epi-chorohydrine).In the present work, two working solutions were used. The first solution was a synthesized phosphoric acid (35% P 2 O 5 and 100 ppm U) used for optimizing the loading process of uranium. The second one was used as a case study for adsorption of uranium from a real phosphoric acid (WPPA) prepared from El-Sebaiya phosphate ore (P 2 O 5 35%, 100 ppm U).The obtained equilibrium data were found to be satisfactory fitted with Langmuir isotherm.A maximum-metal uptake of 56.5 mgU/g AIC was observed at the obtained optimum conditions. Also, elution process of uranium has been achieved at 1 M of 30 ml Na 2 CO 3 solution/g AIC after 15 min contact time. From the latter, a marketable product of sodium di-uranate was prepared.

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The recovery of two rare earth metal ions (REs) [Y 3+ and La 3+ , belonging to heavy and light REs, respectively] was studied using functionalized poly(glycidylmethacrylate) adsorbent (F-PGMA) modified with polyaminophosphonic acid moieties. By using CHNP/O, BET, SEM, pH-titration, XRD, XPS, and FTIR analysis techniques, the structure of the synthesized adsorbent was clarified. The adsorption properties toward Y 3+ and La 3+ were compared and the interaction behaviors were explained with XPS and FTIR analysis. The saturation adsorption capacities (in mmol.g -1 ) have the following order: La 3+ (0.795) > Y 3+ (0.744) at optimal pH0 5.0. The adsorption was endothermic with fast kinetics (180/240 min) and the adsorption half-time (t1/2) 16.2 and 29.3 min for La 3+ and Y 3+ , respectively. Langmuir and pseudo-second-order equations (PSO) fit well experimental data. Also, the possible complexes structures were explained. According to the adsorption test in bi-system solution, KSC(La 3+ /Y 3+ ) was about 1.7. Desorption and adsorbent recycling were successfully achieved using HNO3 solution (0.5 M). The F-PGMA shows high durability over six cycles with desorption efficiency >93% and >95% for La 3+ and Y 3+ , respectively. The adsorption process was described quantitatively using novel three-dimensional (3D) nonlinear mathematical model. The advanced theoretical studies were achieved by the MATLAB software, utilizing a variety of models. The data were then fitted using a successive approximations approach with many trails. The Floatotherm included Van't Hoff parameters model was revels the endothermic and spontaneous behaviors of the adsorption process. Vermeulen model of the binary system indicates that, the adsorption process was achieved with a synergism behavior and the Y element exhibited more competition than La.

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