Patent ID: 8187561

Claim:
A process for recovering compounds having rhenium from catalyst substrates from an ethylene epioxidation process, the catalyst substrates having a silver (Ag) catalyst and rhenium (Re) catalyst promoter, the process comprising: without prior heating of the catalyst substrates, contacting the catalyst substrates from the ethylene epioxidation process with a first liquid solution containing a peroxide to oxidize and remove at least some of the rhenium from the substrates to directly produce a second liquid solution containing rhenium; and isolating at least some of the rhenium by passing the second liquid solution containing the rhenium through a weak basic ion exchange resin to capture at least some of the rhenium on the ion exchange resin, and passing a third basic liquid solution through the ion exchange resin to remove at least some of the rhenium from the ion exchange resin to produce a fourth liquid solution containing compounds having rhenium.