South Africa ptfe 0.2 micron filter for medicine Carbon Dioxide (CO2) Filtration for Cider & Perry Production Emflon® PFRW filters, featuring two layers of Pall 0.2 micron polytetrafluoroethylene (PTFE) membrane, are designed to remove bacteria, yeasts, molds, and particles from gas (CO 2) streams, even in the presence of humidity and moisture.