Kinetics and Thermodynamics Studies on the Recovery of Thorium Ions Using Amino Resins with Magnetic Properties

Magnetic polymeric matrixces were synthesized from glycidyl methacrylate, <i>N</i>,<i>N</i>′-methylenebis­(acrylamide) (MBA), and nanomagnetite particles. The obtained polymers were modified by ethylenediamine (DA) and diethylenetriamine (TA) to produce two amino-magnetic resins named R-DA and R-TA. The recovery of Th­(IV) ions from their aqueous solutions by R-DA and R-TA were studied in the pH range 1–4. Maximum adsorption capacity values of 60 and 84 mg/g of Th­(IV) ions on R-DA and R-TA, respectively, were obtained at pH 3.5 and 293 K. At a solid/liquid ratio (S/L) of 2 g/L, recovery efficiency values of 86 and 95% were achieved from initial thorium ion concentration of 100 mg/L using R-DA and R-TA, respectively. Adsorption isotherms and kinetic and thermodynamic parameters of the adsorption process were obtained and analyzed. Regeneration of the resins was tested by eluting the loaded Th­(IV) ions on the spent resins using 0.2 M HNO₃ followed by washing with dilute NaOH