Gas permeation properties of new type asymmetric membranes

✍ Scribed by Hisao Hachisuka; Tomomi Ohara; Kenichi Ikeda

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 706 KB
• Volume: 61
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19960829)61:9<1615::aid-app21>3.0.co;2-n

✦ Synopsis

We have developed a new type of asymmetric membranes having a homogeneous hyperthin skin layer, which was used a s a polyimide synthesized by 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (GFDA) and 2,2-bis(4-amino phenyl) hexafluoro-propane (BAAF). T h e skin layer thicknesses of the GFDA-BAAF polyimide asymmetric membranes were 40-60 nm, and the porosity was when a defect size was assumed as 5 nm. T h e permselectivity of GFDA-BAAF polyimide asymmetric membranes after silicone coating had a of 40 for C02/CH4 and a flux of 1.0

s cmHg]) for C02, a of 4.3 for 02/N2 and a flux of 2.0 X lo-' [Nm3/m2/h/atm] (=7.1 X [cm3(STP)/cm2 s cmHg]) for 02. These values were constant for large-scale manufacturing.