Membrane Mastery: Nanosize silica speeds up sieve
When separating molecules from one another–whether to purify natural gas or clean wastewater–engineers and scientists usually use expensive techniques that require a lot of energy. A less expensive, environmentally friendly–though not always as efficient–option is to filter molecules with membranes made of polymers, carbon, or ceramics.
Now, a new modification to polymer membranes gives researchers a means to tune certain filters so they separate molecules more quickly and more selectively. The new membranes contain nanoscale particles of silica, Tim Merkel of the Research Triangle Institute in Research Triangle Park, N.C., and his colleagues report in the April 19 Science.