Gas recovery of sulphur hexafluoride

A system and method are provided for recovering a re-usable grade of sulphur hexafluoride (SF6) from a potentially contaminated gas source. The system includes extraction vessels connected to the potentially contaminated gas source. A first cryogenic means reduces the temperature of the extraction vessel to a temperature below the phase transition of SF6 causing a pressure differential which causes the potentially contaminated gas to enter the extraction vessels. The SF6 turns to liquid and/or solid form in the extraction vessel. Non-condensed contaminant gas is evacuated from the extraction vessels. Recovery vessels are connected to the extraction vessel. A second cryogenic means is used to reduce the temperature of the recovery vessels. Raising the temperature of the extraction vessels creates a pressure differential which causes a re-usable grade of SF6 to enter the recovery vessels.