Patent ID: 8795509
Filing Date: 2014-08-05
Classification: C01G,C01P,C22B

Abstract:
1. A process for preparing a pure ammonium perrhenate, the process comprising: producing a first aqueous suspension containing an ammonium perrhenate; adding a stoichiometric amount of a nitric acid to the first aqueous suspension so as to produce a second suspension; introducing the second suspension into a cathode space of an electrolysis cell, wherein the electrolysis cell is divided by a cation-exchange membrane into the cathode space and an anode space; cathodically reducing the nitric acid to a nitrous acid in the cathode space by applying an electric potential; reacting the nitrous acid with ammonium ions of the ammonium perrhenate so as to form an aqueous perrhenic acid; removing potassium ions from the aqueous perrhenic acid; and adding at least a stoichiometric amount of ammonia to the aqueous perrhenic acid so as to produce the pure ammonium perrhenate.