Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4769091 | Hydrometallurgy | 2017 | 30 Pages |
Abstract
The grafting of diethylenetriamine (preferentially to the grafting of serine > cysteine > alanine) onto chitosan (immobilized on magnetic nano-based particles by combined polymer precipitation and hydrothermal treatment) allows synthesizing an efficient sorbent for uranyl at pH 4 (maximum sorption capacity close to 185 mg U gâ 1). Sorption isotherm (regardless of the sorbent) is fitted by the Langmuir equation, while uptake kinetics is well described by the pseudo-second order rate equation. The design of nano-based particles (10-50 nm) allows reducing the impact of resistance to intraparticle diffusion on uptake kinetics and the equilibrium contact time is close to 45-60 min. The super paramagnetic properties of the hybrid materials make their solid/liquid separation quite easy using an external magnetic field. Finally uranyl ions can be desorbed using acidic urea solution (0.5 M, pH > 2) and the sorbents can be recycled for at least 5/6 cycles with a limited loss of sorption capacity (< 9%).
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Chemical Engineering (General)
Authors
Ahmed A. Galhoum, Mohammad G. Mahfouz, Nabawia M. Gomaa, Thierry Vincent, Eric Guibal,