Poly(4-vinylpyridine) resins towards perrhenate sorption and desorption

Abstract

The series of the 4-vinylpyridine and divinylbenzene cationic polymers (4-VP/DVB) in the presence of toluene or toluene and heptane (100 wt.% in respect to the monomers mixture) were synthesised in order to obtain weak base anion exchangers with gel or macroporous structure. The strong base anion exchangers were obtained by its quaternization with alkyl iodide: propyl iodide, butyl iodide and pentyl iodide. The FTIR spectra of anion exchangers were useful to characterize resins and degree of quaternization. The sorption and desorption ability of rhenium, Re(VII), as perrhenate anion from acid solution (sulphuric or hydrochloric acid 0.1 M) were tested in batch and dynamic methods. The sorption of Re(VII) from the solution of 50 mg Re/L reached about 60 mg/g of dry resin in batch method. All the investigated anion exchangers characterize with high selectivity of perrhenate from multicomponent solution containing chlorocomplexes of PGM metals (Pt, Pd) and Au. The sorption ability of PGM metals and Re(VII) is on the same level as from the solution containing only one ion. The dynamic method of sorption allowed to reach the sorption of Re(VII) up 200 mg/g of resin. The desorption of Re(VII) by ammonium (5 wt.%), with the yield about 97%, was possible only from the weak base anion exchangers, where the degree of sorption and desorption is on the same level in the second and other cycles. The sorption ability of Re(VII) on new anion exchanger is comparable to commercial anion exchangers, like Reillex HP.