Separation of N2/SF6 binary mixtures using polyethersulfone (PESf) hollow fiber membrane

PESf hollow fiber membrane was used to recover sulfur hexafluoride (SF₆) from N₂/SF₆ binary mixture gas. To fabricate a hollow fiber membrane, a dry-wet phase inversion method was used. Fiber was post-treated by methanol to increase permeance. Fabricated membrane was characterized by scanning electron microscopy (SEM) and N₂, SF₆ single gas permeation according to temperature and pressure difference. Using N₂/SF₆ binary mixture gas (10 vol% of SF₆), we checked the separation of mixture gas in a manufactured single module according to temperature, pressure difference, and retentate flow rate. The highest SF₆ purity in recovered gas was 50.4 vol% when the pressure difference, temperature, and stage cut was highest in experimental conditions, but the recovery ratio marked the lowest value.