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Technetium(~(99)Tc), a major fission product in nuclear reactors, of high yield, long-half-life and high mobility in the environment must be removed in nuclear fuel reprocessing. Considering rhenium(Re) and Tc are both VIIB elements, Re is a good chemical analogue to ~(99)Tc. Herein, we use Re as a substitution of ~(99)Tc to study adsorption and desorption behavior. Porous 4-vinylpyridine–divinylbenzene-based(4VP–DVB) adsorbent containing tertiary amine groups is synthesized by suspension polymerization and characterized by BET, TGA, SEM and laser particle size analyzer. The adsorbent has high adsorption efficiency toward Re(VII) in 0.1 mol/L nitric acid solution, and the adsorption equilibrium can be achieved in 30 min. The adsorption kinetics of Re(VII)follows pseudo-second-order rate equation, the adsorption isotherm matches well with the Langmuir isotherm, and the adsorption capacity of Re(VII) on 4VP–DVB adsorbent is 352.1 mg/g at 298 K. Thermodynamic study reveals that the adsorption process is exothermic. This adsorbent is of separation convenience when a fixed-bed column is used,compared to the batch adsorption treatment.
Technetium (~ (99) Tc), a major fission product in nuclear reactors, of high yield, long-half-life and high mobility in the environment must be removed in nuclear fuel reprocessing. Considering rhenium (Re) and Tc are both VIIB (99) Tc. Herein, we use Re as a substitution of ~ (99) Tc to study adsorption and desorption behavior. Porous 4-vinylpyridine-divinylbenzene-based containing tertiary amine groups are synthesized by suspension polymerization and characterized by BET, TGA, SEM and laser particle size analyzer. The adsorbent has high adsorption efficiency toward Re (VII) in 0.1 mol / L nitric acid solution, and the adsorption equilibrium can be achieved in 30 min. The adsorption kinetics of Re (VII) follows the pseudo-second-order rate equation, the adsorption isotherm matches well with the Langmuir isotherm, and the adsorption capacity of Re (VII) on 4VP-DVB adsorbent is 352.1 mg / g at 298 K. Thermodynamic study reveals that the adsorption process is of separation. when the separation process is exothermic. This adsorbent is of separation-free when a fixed-bed column is used, compared to the batch adsorption treatment.