Concentration of Tc(VII) from Aqueous Solutions with Filled Fibrous Sorbents

Abstract

Sorption of Tc(VII) on fibrous sorbents filled with finely dispersed anion exchangers (AV-17-n and AN-31-n) and on a chelating sorbent bearing 1,3(5)-dimethylpyrazole groups (POLYORGS-17-n) is studied. The Tc(VII) distribution coefficients (Kd, cm3 g−1) are determined in sorption from simulated nitric acid, alkaline, and saline solutions. The highest distribution coefficients (Kd ∼103 − 105 cm3 g−1) were obtained in sorption of Tc from weakly acidic (≤0.1 M HNO3) and alkaline (0.1–1.0 M NaOH) solutions. In sorption of Tc from alkaline and nitric acid solutions containing NaNO3, POLYORGS-17-n demonstrated the highest efficiency. Tc is totally recovered with the sorbents studied in 10 min. Then it can be eluted with 1 M HNO3. The sorbents AV-17 and POLYORGS-17-n can be used for Tc(VII) recovery from saline solutions like groundwater (pH ∼8).