Cysteine-Functionalized Chitosan Magnetic Nano-Based Particles for the Recovery of Uranium(VI): Uptake Kinetics and Sorption Isotherms

Abstract

Magnetic-chitosan nanoparticles, functionalized with cysteine, were synthesized and characterized by element analysis, FT-IR, XRD, TEM, and vibrating sample magnetometry. The sorbent was tested for U(VI) recovery, considering:

• a. pH effect,

• b. sorption isotherms (fitted by Langmuir equation), and

• c. uptake kinetics (modeled using the PSORE).

Maximum sorption capacity approached 100 mg U g⁻¹. The nanometric size of sorbent reduces the impact of resistance to intraparticle diffusion; this may explain the fast kinetics (equilibrium within 50 min). The reaction is exothermic, spontaneous. The metal could be desorbed using acidified urea solution and the sorbent could be recycled for 5 cycles.

Keywords:

• Cysteine-functionalized chitosan
• uranium(VI)
• magnetic chitosan nano-based particles
• sorption isotherm
• uptake kinetics

Additional information

Funding

This work was supported by the French government through a fellowship (A.A. Glahoum) granted by the French Embassy in Egypt (Institut Français d’Egypte).