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Science 5 July 1968:
Vol. 161. no. 3836, pp. 70 - 72
DOI: 10.1126/science.161.3836.70
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Articles

Charge-Mosaic Membranes: Enhanced Permeability and Negative Osmosis with a Symmetrical Salt

John N. Weinstein 1 and S. Roy Caplan 1

1 Biophysical Laboratory, Harvard Medical School, Boston, Massachusetts 02115

Charge-mosaic membranes are prepared by embedding a single layer of alternating cation and anion exchange beads in silicone resin. Membranes made in an identical manner but containing only one type of exchanger serve as controls. The mosaic membranes are 50 to 100 times more permeable to potassium chloride than the controls; and furthermore they give rise to net volume flow from concentrated to dilute solutions of potassium chloride in the absence of a pressure gradient ("negative osmosis"), whereas the controls exhibit normal osmotic behavior. The negative reflection coefficients of the mosaics suggest potential applications in desalination.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
A New Charge-Mosaic Membrane from a Multiblock Copolymer.
T. FUJIMOTO, K. OHKOSHI, Y. MIYAKI, and M. NAGASAWA (1984)
Science 224, 74-76
   Abstract »    PDF »
Charge-Mosaic Membranes: Dialytic Separation of Electrolytes from Nonelectrolytes and Amino Acids.
J. N. Weinstein and S. R. Caplan (1970)
Science 169, 296-298
   Abstract »    PDF »


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