SF6 Reclaimer from SF6/ N2 Mixtures by Gas Separation with Molecular Sieving Effect

Discussing various methods for SF6 separation from a mixture of low concentrations of SF6 in N2, pressure swing adsorption (PSA) with a suitable kind of synthetic zeolite, which is expected molecular sieving effect, has been selected. This molecular sieving effect, derived from molecular size difference between SF6 and N2, is confirmed by the difference between two equivalent volumes filled with SF6 and N2. Prototype equipment of SF6 separation and liquefaction, about 1 m cube in size and 150 kg in weight, has been assembled and tested. The ability of gas mixture handling is 13 L/min. in average, and the SF6 content is reduced to 0.0% (undetectable level) in separated N2 to exhaust into the atmosphere.