METHOD FOR PRODUCING PERRHENIC ACID AQUEOUS SOLUTION AND POTASSIUM PERRHENATE OBTAINED BY USING THE SAME, AND METHOD FOR PRODUCING AMMONIUM PERRHENATE AND RHENIUM METAL

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 rhenium sulfide to first burning in the presence of an oxygen-containing gas to collect the gasified rhenium oxide; a step of cooling and solidifying rhenium oxide while maintaining a sulfur oxide accompanying the gasified rhenium oxide in a gas state and followed by solid-gas separation to improve the purity of the rhenium oxide; 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.