Feb 22, 2022 · PTFE (Poly Tetra Fluoro Ethylene) Filter Cartridge. PTFE cartridge membrane is used in filtering the highly corrosive solutions such as strong acids, base solution, and solvents. The membrane has about 80 – 95 % porosity & uniform pore size distribution. Moreover, the filtration area of each cartridge is as high as 0.7 m2.