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

Magnetic polymeric matrixces were synthesized from glycidyl methacrylate, N,N'-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.