Method for producing perrhenic acid aqueous solution and method for producing potassium perrhenate, ammonium perrhenate and rhenium metal using the same

摘要

PROBLEM TO BE SOLVED: To provide a method capable of producing high-purity perrhenic acid from rhenium sulfide obtained by treating an acidic solution containing rhenium using a dry process.SOLUTION: There is provided a method for producing a perrhenic acid aqueous solution which comprises: a step of passing an acidic solution containing rhenium through an anion exchange resin to adsorb rhenium on the anion exchange resin; a step of passing an eluent through the anion exchange resin on which rhenium is adsorbed to elute rhenium from the anion exchange resin; a step of sulfurizing the rhenium contained in a solution after elution to obtain rhenium sulfide; a step of subjecting the rhenium sulfide to first burning in the presence of an oxygen-containing gas to generate rhenium oxide and a sulfur oxide and gasifying and discharging the sulfur oxide to obtain rhenium oxide as a burning residue; a step of subjecting the burning residue to second burning in the presence of an oxygen-containing gas to collect the gasified rhenium oxide; a step of cooling and solidifying the gasified rhenium oxide; a step of obtaining a perrhenic acid aqueous solution by dissolving the gasified rhenium oxide in water while cooling with water; and a step of obtaining the perrhenic acid aqueous solution by dissolving the solidified rhenium oxide in water, or heating and gasifying the solidified rhenium oxide and followed by dissolving in water, when the rhenium oxide is solidified.