The flux per volume across selective membranes can potentially be increased by at least five times using corrugated membranes. This increase is important because membrane selectivity is often inversely related to membrane flux. The flux across a selective membrane which is hampered by low permeability can be increased by making the membrane thin and by having a large membrane area per volume, e.g., by using hollow fibers. Where these flux increases are insufficient, membrane corrugations could supply further gains. This paper derives a theory predicting these increases. The theory is verified for pervaporation of aqueous chloroform, ethanol and other solutes across macrocorrugated polydimethylsiloxane membranes. The results supply criteria which must be met by any nanocorrugated membranes. Copyright (C) 2000 Elsevier Science B.V.
Bibliographical noteFunding Information:
We thank Terri Shefelbine and Frank Bates for their work with nanocorrugated membranes. This work was largely supported by the National Science Foundation grant CTS 96-27361. Other support came from the National Science Foundation CTS 94-28755 and the Department of Defense DAA H04-95-1-0094.
- Area per volume
- Gas separations
- Membrane structure