Synthesis of perrhenic acid using ion exchange method

The paper presents results of the study for obtaining perrhenic acid from aqueous ammonium perrhenate solutions by ion exchange. Two ways of perrhenic acid synthesis have been examined: sorption of perrhenate anion on selected anion exchange resins (followed by elution of the sorbed rhenium as HReO4), and sorption of ammonium ion on selected cation exchange resins. The method of ammonium ion sorption on cation exchange resins has proved to be more effective. Using C 160 (H) cation exchange resin, perrhenic acid containing > 300 g/L of Re (after performing concentration in vacuum evaporator) has been obtained, with impurities concentration at the level of: < 1.0 mg/L NH4, ≤ 0.05 mg/L sodium, ≤ 0.20 mg/L potassium, ≤ 0.10 mg/L magnesium and ≤ 0.20 mg/L calcium.