Concentration of rhenium from dilute sodium chloride solutions

The conditions for the desorption of rhenium from the anion exchange resin Dowex 1-x8 by HNO 3 , HCl, H 2 SO 4 and NaOH were determined. The solution (5.0x10 -3 mol dm -3 Re in 0.15 mol dm -3 NaCI) was passed through a column containing 0.10 g of the resin. The total sorbed amount of rhenium was 0.20 g/g of the resin. It was then eluted by the corresponding eluent in the concentration range up to about 3.0 mol dm -3 . The highest elution efficiency and the most favourable elution profile were found with 3.0 mol dm -3 HNO 3 . Over 77 % of the sorbed rhenium was found in the first 5 ml of the eluate. Practically all the rhenium was recovered with 20 ml of the acid. Under the given experimental conditions, HCI and H 2 SO 4 were less favourable while NaOH was not applicable, due to very low efficiency of rhenium elution.