Fine Purification of Rhenium to Remove Polyanions during Selective Desorption from a Strongly Basic Anion Exchanger in Schemes for Obtaining Ammonium Perrhenate

We studied the conditions for separating rhenium and polyanions (molybdenum and tungsten) by selective extraction of rhenium from the phase of saturated gel-type strongly basic anion exchanger by tertiary amine solution. Rhenium passes quantitatively into the organic phase under both dynamic and static conditions. The optimal parameters of this method of extractive desorption of rhenium are designed, which ensure complete removal of polyanions and other accompanying impurities. In order to make rhenium further pass into the aqueous phase, the extractant is treated with ammonia solution. Ammonia–salt mixtures are recommended to be used for desorption of molybdenum or tungsten polyanions from the strongly basic anion exchangers.